Time for a Change
by CrimsonStarbird
Summary: As per the original Eclipse Gate plan, Lucy and Yukino are sent back in time to kill Zeref before he becomes immortal. Eight-year-old Zeref has something to say about this. COMPLETE.
1. Past

_**A/N:** Hello all, me again. I wasn't intending to upload something new so quickly, but I wrote the first chapter of this on a whim, and it evolved (somewhat unexpectedly) into a short story about Natsu and Zeref. So, in honour of the final season starting last week, here it is. _

_This story will be in four chapters. The first one is silly, then it gets serious; you know the drill. I aim to update every Sunday night as usual, but between work, exams, and the long chapter length, it might not happen. I'll do my best._

 _This fic is set at the end of a slightly different Grand Magic Games arc. There has been no Future Lucy and no Future Rogue, so in the absence of any other time travel shenanigans, Arcadios and Hisui are going ahead with the original plan to send people back in time to kill Zeref before he becomes immortal. Now, without further ado, I hope you enjoy this little story! ~CS_

* * *

 **Time for a Change**

By CrimsonStarbird

* * *

 **-Past-**

Lucy was nervous.

It wasn't because they were about to attempt brand new experimental magic on the orders of a Colonel who wasn't even a mage himself, in conjunction with a mysterious evil door that had just been _found_ beneath the palace.

It wasn't because no one had ever travelled through time before, and thus they had no real idea of what could and couldn't be changed, and what would and wouldn't wipe out the present as they knew it.

It wasn't even because there was a very real chance that she might tread on a butterfly and thus somehow prevent herself from being born.

No, Lucy was nervous because Yukino _wasn't._

In the short time Lucy had known the ex-Sabertooth mage, she had reached two conclusions about her: that she was a nice enough person, but that she had an unfortunate habit of taking things to extremes. When the other competitors were making harmless wagers on their fights, Yukino had bet her life. When she lost one battle, she had tried to give her precious gold keys away to a total stranger. When she was expelled from her guild… she had immediately thrown her lot in with Colonel Who-Needs-Temporal-Continuity-Anyway Arcadios and his completely sane plan that stood no chance whatsoever of accidentally destroying the world.

To be honest, Lucy hadn't been particularly enthusiastic about the Colonel's plan to go back in time and try to murder the most dangerous man who had ever lived even _before_ she had found out that she, as one of the two Celestial Spirit mages whose keys were needed to open the Eclipse Gate, was therefore one of the two people to whom this delightful task fell. She had only gone along with it because she knew that if she didn't, Yukino would go on her own – and she, Lucy was beginning to suspect, wouldn't hesitate to step on that butterfly of chaos if she thought it was working with Zeref.

Never mind that this whole affair had stopped Lucy from participating in the finale of the Grand Magic Games, because she was too busy making preparations with Colonel Arcadios and Princess Hisui. Never mind that she had been too nervous about messing with forces beyond human comprehension to savour her guild's victory. No, _someone_ had to make sure the well-intentioned but completely mental Colonel who'd managed to get his hands on a time machine wasn't about to turn the world into one giant paradox, and it looked like it was going to be responsible ol' Lucy Heartfilia again.

She stole a glance at Yukino. Her face may as well have been carved from stone by a sculptor who had never been backstage before the curtain rose, or opened a letter containing exam results, or been told he was to be the guinea pig for bloody _time travel._ There wasn't a trace of nerves in sight. Her eyes were set with the determination of mythical heroes. The sword and armour of a soldier of Fiore suited her far better than that ostentatious feathery cloak she had been wearing during the Games, and Lucy wished she could have meant that as a compliment.

Yukino must have sensed her looking, because she finally broke her staring contest with the Eclipse Gate to ask her, "Are you ready, Lucy?"

Not trusting herself to speak, Lucy gave her a watery smile. It was a shame her zodiac keys had already been taken by Arcadios, or she and Virgo could have been on the other side of the planet by now. She was forced to watch as the Colonel responsible for this madness inserted the keys into the door like he was laying out the steps to the gallows. There was power already building in the Gate, in the gathering storm, in the blood-red moon above – why no one else could see this blatant bad omen Lucy had no idea, but then these were the same people who thought using a sinister artefact of unknown provenance that they'd unearthed from the execution ground beneath the palace was a good idea, so maybe she was the fool for still expecting them to show any kind of common sense at this stage.

As the Eclipse Gate swung open to unleash blinding light into the courtyard, she hypothesized, optimistically, that time travel might be completely safe. Maybe the universe had a built-in mechanism to protect itself from paradoxes. Maybe they'd be able to stroll into the past, find Zeref, and return to a present that the universe had strived to keep exactly the same.

Following Yukino into the light, Lucy decided that it was a bad day indeed when coming face-to-face with the notorious Black Mage was the best-case scenario.

* * *

Something nudged Lucy's arm.

That isolated sensation triggered a cascade of others – a pressure on her front, a dryness in her throat, an unyielding darkness in her vision – and after a moment of disorientation, during which time travel made its debut entry onto her list of favourite transportation methods in a solid last place, she concluded that she was lying on the ground with her eyes closed. Rectifying the former seemed like it would require more energy than she had, but the latter was easy enough, and her eyelids fluttered open.

At first, the world was so bright that she wondered if the Eclipse Gate had dumped her in some psychedelic in-between spacetime. Slowly, though, her swirling vision adjusted to a carpet of green grass and a ceiling of blue sky – and an upside-face that appeared suddenly in front of her own.

She let out a startled cry, and so did the face. It vanished again, and she scrambled backwards, overruling her dizzy head's attempt to stage a mutiny as she pulled herself into a sitting position. The world dissolved into colour, and when it settled once again, the picturesque sky-and-field backdrop had acquired a stark anomaly in the form of a young boy, no older than eight or nine.

He was a living juxtaposition of dark and light: he wore a black sash draped across a white tunic, the old-fashioned clothes looking oddly formal even as he bounced on the balls of his feet with poorly suppressed excitement; his eyes were as dark as midnight, and yet somehow they were the brightest, most dazzling things she had ever seen.

"You're alive!" he exclaimed.

Lucy gave a tentative nod, not wanting to attempt anything bolder and invoke the gods of irony. Glancing around, she saw Yukino struggling to sit up on the grass beside her. Beyond her lay a smattering of trees and the spires of a city on the horizon. Behind them both, at the end of a trail of still-smouldering brown grass, stood the accursed Eclipse Gate – closed, silent, and, bizarrely, in the middle of a field instead of the palace courtyard she had left.

Turning back to the boy, she asked what was undoubtedly the most clichéd question of her adult life – but as she was also the first person outside of science fiction legitimately able to ask it, she felt her actions were justified. "What year is this?"

"X363," he answered at once. "Why, what year was it last time you checked?"

"X791," she told him.

She was expecting disbelief. Or denial. Or even plain confusion.

What she was not expecting was for the boy to leap into the air and scream, "YES!"

"Uh… what?" Lucy wondered.

"Yes, yes, YES!" he shouted, bouncing higher with every word. "I did it! I actually did it! Ha! I told you it was possible! I told you all! Oh, you are going to regret laughing at me now! Fame, fortune, funding, _here we come!"_

His words dissolved into laughter bordering on maniacal. Lucy exchanged glances with Yukino as the two got to their feet. Neither of them knew quite what to make of the boy who was still cheering like… like he'd just survived the plague, or traded a cow for some magic beans, or whatever it was children had to celebrate back in the fourth century.

"Excuse me," Lucy interrupted, "but what, exactly, did you do?"

"Invented time travel!" he told her brightly. Before she could respond, he pivoted towards the city on the horizon, cupped his hands around his mouth, and bellowed, "Take that, Dean Osvalio! Take that, you and your _I'm sorry, but we don't have the budget to fund research with no real-world applications_ and your _ooh, your research is angering Ankhseram_ and your _no, you're too young to borrow our arc welder –_ well fine, I'll just invent a new kind of concentrated electricity magic and _do it by hand!"_

He sucked in a deep breath and spun back to face them cheerfully. "So, what's the future like?"

"Whoa, let's just take it back a few steps there, kiddo," Lucy overrode him. "What do you mean, _you_ invented time travel?" _She_ was the one who had been shoved through an experimental spacetime portal, and she'd be damned if she wasn't going to get the recognition for it.

She had never before seen anyone below the age of eighty pull off such a look of condescension. "You see that huge magical gate you just came through? The one that can connect to any point along its own timeline? Well, I built it."

" _You_ built it?"

"Oh, don't _you_ start. Yes, I worked out the theory of true temporal magic myself, and then I built it myself, and then I worked out how to open it by myself – not that I would have _had_ to if those bloody buffoons at the Academy hadn't cut my funding-"

"Language," Lucy reprimanded him.

He pulled a face. "It's not a swear word in X363."

"First of all, you're lying, and second of all, you shouldn't even know what swear words _are_."

"Yeah, well, I shouldn't know about conjugate spacetime stabilization either, but if I hadn't stolen those books from the Dean's library, you wouldn't be here now."

Lucy folded her arms, taking a weird kind of pleasure from the significant discrepancy in their heights. "What are you, like six years old?"

"Eight years and two-hundred-and-thirty-four days," he replied promptly.

"What, no months?" she teased.

"I see no merit in using such an arbitrary and inconsistent unit of measurement."

"Years vary in length too, you know."

"One part in three-hundred-and-sixty-five is an acceptable level of variance. It's half the error I allowed for the Gate of Time, and you two made it here in one piece, didn't you?"

"What do you mean, _in one piece?"_ Lucy yelped, but Yukino stepped forward and placed a hand on her shoulder.

"Lucy, as fascinating as this is-" She turned to the boy, and Lucy wondered how he didn't shrink away from the stone-cold resolution in her eyes, "-and as nice as it has been to meet you, we have an important task ahead of us – one which we must perform without further ado."

"You're absolutely right, we do!" the boy agreed, before Lucy could say anything. "You two have to come to the Academy with me and prove that my Gate of Time works!"

The longer Lucy could put off their doomed quest to kill the most terrifying mage in history, the more time she had to come up with a plan to get them back to the present without incident. "How are we going to do that?" she asked the boy, steadfastly ignoring the glare Yukino was sending her from the side.

"By telling them about the future!"

Lucy shrugged. "There's not much to say, really. Dragons are extinct, and there are way more guilds… do you even have guilds in your time?"

The boy waved his hand impatiently. "Not useless, vague things like that. What are you, amateurs? You'll need to tell them something concrete and locally testable. For instance, what's going to happen tonight?"

"Why would I know what happened on some random day four hundred years ago?" Lucy bristled.

"Because this _isn't_ some random day four hundred years ago! It's the day I invented time travel!"

"No, it isn't! Yukino and I were the first people to travel through time – in X791!"

"Yes – _to X363!_ Time travel is possible _right now,_ and once I've shown you to the Academy, today will go down in history as the day I proved that the human race is no longer imprisoned by linear time! In the future, everyone will remember what they were doing at the moment I made my announcement! Some scholars in the Academy are bound to become famous enough to publish autobiographies…"

Misinterpreting Lucy's disbelief, he amended, "No, you're right, they're morons, the lot of them. Still, once _I_ have achieved world-renown, I'm sure they'll all stake their own meagre claims to fame by pointing out that they worked in the same lab as me – _before they were so jealous of my success that they claimed they were scared of unstable magic and made me build my Gate in a bloody field!_ – and then when they publish _their_ autobiographies, they'll definitely include what they were doing on this most transcendental of days…" He blinked. "Won't they?"

"I hate to break it to you-" That was a total lie; Lucy was leaping at the chance to shoot him down, "-but, no. No one had so much as hinted that time travel was possible in academic writings before we came back through the Gate. This day is not going to go down in history in any shape or form."

"How peculiar." The boy stroked his chin, a gesture somewhat undermined by his lack of beard. "Well, time travel _is_ a completely uncharted area of research. I had assumed the future would self-correct for adjustments to the past, but its behaviour seems to be more mysterious than I thought. Evidently just inventing a time machine isn't enough – the whole field of time magic remains in dire need of my genius."

Lucy rolled her eyes. No such playful gesture slipped through Yukino's marble exoskeleton, however, as she interrupted, "Lucy. We do not have time for this."

"Actually," the boy interjected helpfully, "thanks to my invention, time is the one thing of which you now have rather a lot."

"You're never going to stop going on about that, are you?" Lucy sighed.

"No. Why?"

"Has it occurred to you that the reason why no one knows you invented time travel on this day is because you annoyed the professors at your Academy so much that they murdered you and buried the evidence?"

"That did occur to me, until I realized that anyone so tempted would be forced to conclude that the benefit to all humanity of keeping me alive outweighs any petty jealousy they might feel at not being able to keep up with my brilliance."

Lucy raised her eyebrows. "Don't count on it, kiddo."

"Lucy." Yukino spoke in a tone that sent shivers down her spine.

"Alright, alright…"

Lucy turned her attention away from the infuriating boy and his no-less-life-ruining Eclipse Gate, and scanned their surroundings. The distant city was likely to be their best bet. They could acquire information, pick up era-appropriate clothes, and keep a low profile as they decided how they were going to track down and destroy the hopefully-not-yet-immortal Black Mage Zeref… no, it still wasn't sounding any less ludicrous.

"So, what's this super-serious quest you've come back four hundred years to complete?" a cheerful voice butted in, as the boy popped up in front of them again.

"That is none of your concern," Yukino retaliated.

"Since you've hijacked my Gate of Time to carry it out, I rather think it is," he objected, folding his arms. "I was only opening it to see if it would work, expecting to find tomorrow's me on the other side – who, might I add, would have presented a _far_ more convincing case to the Academy's funding board than you two amateurs. So, since you've effectively scuppered my chances both of getting the research grant I deserve _and_ holding a conversation with my only intellectual equal, the least you could do is tell me why."

Yukino snapped, "We're here to destroy the most evil man in history before he can ruin our future!"

"Oh." To her surprise, the boy's gaze dropped towards the ground – and then, inexplicably, he offered his wrists up to them, as if expecting a set of handcuffs to be slapped onto them at any moment. "You'll be here for me, then."

Yukino stared. Lucy clapped a palm to her forehead. "You're eight years old, and you've already decided you're going to be the most evil man in history?"

"Genius is always misunderstood," he told them sadly. "I knew this would happen, sooner or later."

"You do realize that not everything in the world is about you, right?" Lucy asked, only a fraction sarcastically.

"But _I_ invented _time travel!"_ he insisted. "Ever since I started making headway with my research I've been expecting crusaders to show up from the future, warning me away from this path with tales of horrific paradoxes and temporal inconsistencies… now that I think about it, that must be why _you_ were on the other side of the door, rather than tomorrow's me! You're from a future torn apart by the temporal collapse I caused, so of _course_ you know how to hijack a time portal!"

"Or maybe future-you realized what a brat you are and boycotted the meeting."

"Let's go, Lucy," Yukino intervened. "We're wasting time here."

"For once, Yukino, I find myself agreeing with you."

Again, however, they didn't get more than a few steps towards the city before the boy popped back into their field of view. "Are you _sure_ it's not me you're after?" he wheedled.

"Oh, of course, I totally forgot about our secondary mission to destroy the most irritating person to have ever been born," Lucy snarked.

"I mean, I didn't _intend_ to destroy the world… but let's face it, out of all the mages in the Academy, I'm by far the most likely to have done it by accident. That's the price of being a true pioneer."

There was a slightly unsettling light in Yukino's eyes. "On second thoughts, Lucy, perhaps we shouldn't be so quick to rule him out. We don't know enough about this era. It may well be him we're looking for."

Lucy's palm returned to her forehead. "For the love of all that is holy, please do not encourage him."

She did not listen. "What's your name, child?"

"Zeref Dragneel," he replied promptly.

"Zeref!" Yukino exclaimed. Her hand jumped to the hilt of her sword – surprising Lucy, who hadn't realized it had ever left – and pulled it from her sheath. The army-issue blade slid free with worryingly little protest. "At last, you're right here before me-"

"Whoa, whoa, whoa, hold on a minute," Lucy interjected. "Did you say Dragneel?"

"That's right!" he chirped.

"Huh. My best friend's a Dragneel. I wonder if he's your distant descendent."

The boy pulled a face. "Eww. Eww, no."

"He's not _that_ bad," Lucy objected, eyebrows raised.

"No, no, no. That's not happening. Children, _eww."_

" _You're_ a child!"

Offended, he folded his arms. " _I'm_ a prodigy. It's completely different."

"It really isn't, kiddo."

"Lucy, stop getting side-tracked!" Yukino snapped. "Zeref has to die, right now!"

"Wait, I have to _die?"_ the boy echoed disbelievingly.

Lucy frowned at him. "What were you expecting when you decided to confess to ruining the future?"

"Well… I figured you'd drag me back to the future to stand trial before a panel of bitter, jealous judges, to whom I would deliver a rousing speech about the importance of free research to defend my actions, until they, reminded of the passion for temporal magic they once had, are moved to set me free and return me to my own time-"

"You have put _way_ too much thought into this."

He shrugged. "I told you, I've been expecting something like this to happen ever since I decided to invent time travel."

"You know, it's kind of amazing how even _your_ head isn't big enough to stop sarcasm from going right over it."

"Stop the what now?"

"Precisely."

A hiss and flick of air forestalled his response; Yukino's blade carved an arc safely short of the bickering pair, but they both flinched nonetheless. "Lucy. Take this seriously."

"Surely _you're_ not serious about this, Yukino!"

"Deadly serious." There was no fracture to let doubt into those flawless marble eyes; there was no more hesitance about her than there'd been when she had been in his position, and Kagura was the one holding the blade. "I'm putting an end to this."

She took a step forward. Zeref took a step back. Bright black eyes seemed to dim for the first time as they focussed on the Celestial mage's borrowed steel.

"Yukino, stop it!" Lucy objected. "You're scaring him!"

"Good. Maybe then he'll understand what it has been like for those of us growing up in his shadow… right before he pays for it with his life."

Zeref's protest came out as a helpless tumble of words. "But- but you can't kill me!"

"Why not, fiend?"

"Because of the paradox!"

"What paradox?"

"Well, you only came back in time because of what I did in the future, right? So if you kill me, then I won't be able to do those things, so you won't come back in time, and then I'll be free to do them again! Me being dead and you being in the past are incompatible! The very fact that you're here means that I can't die! The paradox won't allow it!"

Yukino considered this garbled explanation for several frightening moments. "You just told us that you didn't know how time worked."

"I'm… ninety-nine percent sure it works like that."

"Ninety-nine percent sure?"

He swallowed. "Uh-huh."

"Ninety-nine percent sure," she echoed, bringing the blade slowly to rest an inch away from the boy's quivering neck, "that _the paradox_ is somehow going to stop this sword from cutting your throat?"

His gaze darted to the sword and back. "Ninety-eight percent. Maybe ninety-seven…"

"Let's test that hypothesis, shall we?"

The blade sang – a hymn of death drowned out by Lucy's screech. "That's enough, Yukino!" Not believing for a second that her words would be sufficient, she caught the other mage's wrist, forcing the sword to a halt.

"See?" Zeref said, with a tremulous smile. "The paradox made you do that."

"It wasn't the paradox, it was something called _common sense_ , which neither of you two seem to have!" Lucy exploded. "Yukino, he – is – a – child! How can you even _think_ about killing him in cold blood?"

Yukino gave her a mutinous look, whose only effect was to make Lucy tighten the grip on her sword arm. "I start by thinking about how he's done so much worse."

The shadow flitting across the boy's expression didn't go unnoticed by Lucy, but the last thing she wanted was to give him the chance to open his mouth again. Jumping in before he could, she argued, "But he _hasn't_ done those things! Not yet! This is unfair, Yukino, and it's cruel. He's a defenceless child."

"Which was the whole point of us travelling back four hundred years in the first place!"

"No. Not like this. _This_ Zeref hasn't done anything wrong, Yukino. I can't let you do this."

The mage-turned-soldier snapped her wrist out of Lucy's grasp, lifting the razor-edge of her sword. That barrier of lethal steel symbolized everything that stood between them. "Why did you come back through the Eclipse Gate, if you never had the nerve to see this through?"

"I came back to stop you from destroying your soul, and/or the space-time continuum!" Lucy shouted. "We have _no idea_ what will happen if you murder Zeref as a child! The present we left might cease to exist!"

"It's a risk I am willing to take."

" _Why?_ Why did _you_ come back to the past, Yukino? You're not like this – I know how highly your Spirits think of you, and I know how much you care about them in return. You're not a cold-blooded killer."

Quietly, she responded, "For my sister, I could become one."

"Oh."

It wasn't Lucy who had answered, however. That sad little word didn't seem to belong to the self-important brat they had met on this side of the Gate, yet it was Zeref who continued, "I can kind of get that. There's nothing I wouldn't do for my little brother."

"You have a brother?" Lucy inquired.

"Had. He died."

"Oh… I'm sorry."

"Don't be. It's only a minor setback." At Lucy's startled look – she had meant to go for _quizzical,_ but her cheek muscles apparently took offence at his depiction of death – he waved his hand dismissively. "I'm going to bring him back to life, you see. That's what all my research is for."

Then he tilted his head to the side, and amended, "Well, not _all_ of it. I figured out pretty quickly that the Gate of Time would only let me go forward from the moment it was complete, so I couldn't go back in time and save him, but my research into time magic was far too interesting to abandon, so I built it anyway. Besides, once I've proven to those numbskulls on the funding committee that it works, they're all but guaranteed to authorize that grant I need to start looking into alternative power sources for the R-System-"

"So what?" Yukino overrode him fiercely. The marble was cracking now, and it wasn't raw humanity hidden underneath, but spitting, surging lava. "Am I supposed to feel _sympathetic_ for you? You lost _your_ family, so that gives you the right to take everyone else's families away?"

"Of course not! I wouldn't wish that on anyone! In fact, it's _good_ that it happened to me, because no one else would have the skill to bring their loved ones back to life! My brother, bless him, he was the sweetest thing, but he couldn't tell one end of a Nezothine Transposition Function from the other-"

"I lost my sister because of you!" she roared.

Zeref folded his arms crossly. "Well, it must have been an accident, because I'd never do anything like that on purpose."

"How _dare_ you claim-"

"Besides, isn't there an easy way of solving this that doesn't involve me being murdered? Tell me who your sister is and what she looks like, and when I meet her, I'll make sure that I don't do anything to harm her. Or, better still, I'll walk very quickly in the opposite direction. How's that? That way, whatever I did to her won't happen, and it also doesn't involve any major changes to the timeline which may or may not shatter reality as you know it, depending on how the laws of time travel work."

"See? A compromise," Lucy remarked, hoping her sigh of relief wasn't too audible.

"Oh, but what if it's one of those self-fulfilling prophecies, and by trying to avoid it, I end up making it happen?" Zeref wondered. "What if she's an ambitious young scholar who is desperate for me to collaborate with her on a research project, and I keep refusing to meet with her because I'm worried about hurting her, until she becomes so depressed by my rejection that she takes her own life? Though, honestly, if someone's devotion to their work is so weak that the opinions of others are enough to make them quit, they have _no_ business being in magical research-"

Lucy clamped her hand over the boy's mouth. "You may know a lot of things, kiddo, but the class on _when to stop talking_ is one you really shouldn't have skipped," she hissed.

"Mmmpf!" Zeref protested.

"It's not as simple as that." Yukino scowled at them both, but she didn't seem angrier than before – which was probably because it wasn't physically possible, but Lucy would claim it as a victory nonetheless. "My sister… she never met you, exactly."

Frowning, Lucy added, "That's a point, Zeref. Why would you assume you did something to her sister personally, when she won't even be born for another four hundred years?"

Zeref shrugged. "You're talking to the person who invented time travel, remember?"

"Touché. Though, as I've said before, you _didn't_ invent time travel. It wasn't a thing until we left X791."

"It's not my fault that the timeline is being slow to update! Look, I've moved Unravel The Mysteries Of Time up several places on my to-do list; what more do you want?" His expression became more thoughtful as he glanced towards Yukino. "But if I never met your sister, how did I cause her death?"

"The same way you killed millions," she said bitterly. "My sister and I lived in a small fishing village, but we had big dreams. Ever since we found Pisces's key in a shipwreck, we'd been planning our adventure to unite all the zodiac keys and become the greatest Celestial Spirit duo in the kingdom… and then, one day, a ruthless cult swept through the village. My sister gave me the key and went to distract them, so that I – and our dream – could survive. They kidnapped her as a sacrifice for the Black Mage Zeref."

In the corner of her vision, Lucy saw the boy's eyes widen, though for once he had the good sense not to interrupt.

"For years, I searched for her. I didn't want to believe that she was gone. When I heard about the fall of the Tower of Heaven, I had hope for the first time in _years_ , because the culprits sounded exactly like that foul cult… but then I spoke to the survivors. I found some who remembered my sister. But they also remembered the _accidents_ that used to happen to the children who wouldn't bow to the slavers, who wouldn't accept Zeref as their god… she was one of those who'd been snatched from the cells in the night. No one ever saw her again."

Slowly, she raised her sword once more, tip angled towards the folds of the boy's archaic clothing. "I couldn't do anything for her while she suffered, all that time. Now, I finally have the chance to get her back."

Zeref didn't look afraid in that moment, trapped between the sharp blade and sharper words. Rather, he looked lost. His brow was furrowed, as though a mathematical problem he was certain he'd understood had come out with an impossible solution.

"But I don't think there's anything I can do about that," he admitted. "Not unless I was specifically telling those people to go around kidnapping children – and I'd never do that! Not even for research purposes! What's the point of saving my brother if it means other people have to go through losing their family in return?"

Yukino looked murderous, and given that she was currently pointing a sword at a boy Lucy wasn't particularly fond of but who absolutely didn't deserve to be murdered, Lucy couldn't help but add her own plea to his cause. "Yukino, I'm so sorry to hear about your sister, but we met the people involved in the Tower of Heaven, and Zeref really didn't have anything to do with it. Not even our time's Zeref. The cult was made up of dark mages who were obsessed with the legacy of the Black Mage, not with- well, with the real Zeref."

"Which is why I am going to cut off that legacy before it can begin," she vowed. "If the Black Mage never existed, he can't have had any disciples, and the cult which murdered Sorano will never be formed."

"I- I'm not sure that will really solve the problem," Zeref ventured. Lucy tensed, but he seemed earnest enough, so she let him speak, only crossing the fingers of one hand behind her back.

"Of course you'd say that!" Yukino snapped.

"But if I don't exist, cults like that will just use someone else to justify their actions, right? I mean, if they can interpret _my_ research as evil, they can do it to anyone!"

Yukino's sword trembled. "You _are_ evil!"

"No, he isn't!" Lucy protested. "He's insensitive, infuriating, and convinced that the world revolves around him, but he's not evil. Not right now. And he's certainly not responsible for the tragedy that happened to your sister. Killing him won't make anything right, Yukino. Worst case scenario, the entire future will disintegrate. But even in the best case scenario, we'll return to that future responsible for the death of an innocent child, no better than the villains who took your sister in the first place."

More and more glowing cracks appeared in the marble of her mask, white-hot scars carving themselves upon her skin. "Then who am I supposed to blame?" she yelled. "I've been training all this time- I joined the strongest guild- I've gambled everything-"

"Maybe just… don't?" Zeref guessed, glancing anxiously from one to the other. "You don't _have_ to blame anyone for what happened, do you?"

"So I should just _forget_ about her?" she howled.

"No, but imagine that it was the other way round, and you'd stayed behind to ensure that your sister got away safely. Would you want her to risk the integrity of the timeline-"

"And her very humanity," Lucy added quietly.

"-on an act that has no guarantee of saving her? Would you want her to spend all her time hung up on your death, rather than living her own life?"

"Isn't that exactly what _you're_ doing with this brother of yours?" Yukino shot back.

The boy's mouth opened, and closed again without a sound. He glanced at Lucy for help, who shrugged, more to see how he would answer than because she didn't know.

Eventually, he managed to choke out an uncharacteristically inarticulate defence: "That's- that's different!"

"Different how?"

Once again, his gaze flickered pleadingly to Lucy. For the first time since they'd met, he was trying to be sympathetic, to understand someone outside his own little world, and she couldn't help but relent. "It's different, Yukino, because he's smiling."

"What?" Yukino blinked.

"What?" Zeref echoed.

"Look at him. He loves his research. In fact, to be quite frank, he's so enthusiastic about it, it's sickening. He invented a functional time machine not because it would bring his brother back – he already knew it wouldn't – but because he _could;_ because he found it fascinating and he wanted to see if he could do it. Show me a timeline where his brother doesn't die, and if Zeref isn't a member of that Academy regardless, I'll bake my zodiac keys in one big celestial pie and eat the lot."

"I used to come here when my brother was still alive, too," he piped up, genuinely helpful for the first time. "He'd distract the librarians for me while I stole books."

" _Borrowed_ books, right?" she frowned at him.

"Well, I did always return them eventually, so yes, let's go with borrowed."

Fighting the urge to roll her eyes, she turned back to Yukino. "But you, Yukino – would you have wagered your life against Kagura if you weren't so determined to prove to the world that you were as ruthless as the villains who killed your sister? Would you have sided with Arcadios and his morally reprehensible, more-dangerous-to-the-present-than-anything-Zeref-ever-did time travel plot, if you hadn't convinced yourself that it involved the slightest chance of seeing your sister again? I've never seen you smile, Yukino. I don't think this is what you want at all."

"But all the things he's done- all the damage he'll keep doing to our future, while he lives-"

"That doesn't justify killing him now," Lucy told her steadily, confident now that Yukino _wanted_ to believe her. "And besides, there's too much I love in our time to gamble it on a world where Zeref doesn't survive. If not for Deliora, I wouldn't have met Gray; if not for Zeref's legacy, awful as it is, I wouldn't have met Erza or even _you_ – heck, if not for all the many children Zeref is going to have-"

" _Hey!"_

"-odds are, I'd never have met Natsu, so it's not all bad."

"Huh," Zeref remarked. "That's a coincidence."

"What is?"

"Natsu was my brother's name."

"Aww, that's cute, you're even going to keep the name in the family!"

As the boy pulled a disgusted face, Lucy took advantage of his moment of silence to turn back to Yukino. "Where was I-? Oh, Yukino, I think you know that this is wrong." Gently reaching out, she freed the blade from Yukino's unresisting fingers and slid it back into the scabbard by her side. "Let's agree to leave the past in the past, and make the most of the present we have."

"I…" Yukino sniffed. Even more frustrated by her attempt to be stoic than by everything that had come out of Zeref's mouth put together, Lucy rolled her eyes – they sure were getting a lot of exercise today – and pulled her into a hug.

"Hear, hear!" Zeref said enthusiastically, clapping both of them on the back.

"Don't push your luck, kiddo," Lucy growled at him. "I can still change my mind."

He muttered something about paradoxes and then, thankfully, fell silent. There they remained for a while, until Yukino wiped her eyes once and pulled away from Lucy to face the boy. He swallowed apprehensively, but she just said, "I am truly sorry for threatening you. Thank you for helping me see sense."

"That's okay. I'm sorry about your sister. If I see any evil cults, I'll be sure to report them straight to the police."

A tiny smile touched the Celestial mage's face. "Thank you. I appreciate the gesture."

Startled, but pleased, the boy smiled back at her. Lucy found herself wondering what had happened to make him into the villain of their age. Not even he could answer that. Not he, who had taken his brother's death as a challenge, and found all the wonder of the world and more in the mysteries of time and magic.

"Lucy." Yukino's tone, far gentler than Lucy had heard from her before, cut into her thoughts. Her face seemed softer, too – her cheeks were still as pale as marble, but they were creased with new warmth. "I believe we should return to our own time."

Zeref clapped his hands together. "Well, fortunately for the two of you, and in spite of your frankly discourteous insistences that I didn't… I am, in fact, the man who invented time travel. I can get you home easily enough."

He gestured to the Eclipse Gate behind them. Standing as it did in the middle of a field, it looked both less and more impressive than the Gate which had been raised to the courtyard of the palace in their time – less, because it lacked the intricate design work and imposing grandeur; more, because it was so out of place that it could only be magical, as defiant and unique as the man who had built it. Boldly it shone in the sun's glorious light-

"Hang on a minute," Lucy started. In spite of that same sun's glow – or perhaps even because of it – chill dread was rising from her stomach. "I thought the Gate only worked during eclipses."

"What? Who told you that?"

Zeref sounded outright offended by the objection, and she couldn't help growing defensive. "Everyone did! Plus, you know, it's in the name!"

"How does 'Gate of Time' imply that it needs an eclipse to work?"

"It's not called the Gate of Time! It's called the Eclipse Gate!"

"I think I know what my own invention is called, thank you very much. Besides, why would I build a device with such an obvious design flaw?"

"So… it works all the time?"

"Of course it does!"

"Lucy has a point, though," Yukino joined in. "That's not what we were told at all."

"Well, you were _also_ not told that I made the Gate, and thus _invented time travel,_ so you're clearly not a reliable source of information," Zeref countered. "I would listen to the person who built it, if I were you. I can open it for you now with no problem at all."

Lucy and Yukino exchanged glances. "I suppose you'll tell us that you don't need the zodiac keys either…"

"Need the what now?"

"How about magical energy?" Lucy tried. "In our time, the Eclipse Gate needed to steal magic from thousands of mages to be able to open…"

"Oh, that. Well, it doesn't need as much as you're probably thinking, but it does need _some_ …" He shuffled over to the Gate, rummaged around in the grass behind it, and lifted up a pipe that had been clumsily painted green for camouflage. One end was attached to the base of the Gate, while the other snaked away in the direction of the city. In a whisper, he continued, "There's a big crystal power source underneath the Academy that I'm not supposed to know about."

"That's stealing," Lucy told him flatly. "I can totally see why they exiled you to a field. Also, did I call you innocent earlier? I must have meant 'quintessential prototype villain'."

Yukino, however, had other concerns. "Will it still have enough power to activate the Gate?"

"Sure. As long as no one else is using it, I calculated that there would be enough magic to open it twice before it dies – once today, and once tomorrow, thus allowing tomorrow's me to walk into today and present our findings to the Academy. I opened it once, and got you two instead. I can open it once more, and as long as it's opened from your end too, where it has its own power source, I see no reason why it wouldn't connect back to that time."

"Arcadios and the others are set to re-open the Gate once we've been gone for five minutes, as they count it," Lucy confirmed.

"That should be fine, then."

"Still…" Lucy shook her head. She couldn't believe she was hesitating, when she had finally reached the end of this ridiculous quest, but… "If you use the last of your magic reserves to send us back, you won't be able to prove to the Academy that you invented time travel."

"Of course I will. You're going to come with me right now and talk to them before you go!"

"What?" she yelped, immediately regretting her moment of weakness. "No, we're not! I have to get Yukino home before anything else goes wrong – 'wrong' being anything from your buddies in the Academy deciding to imprison and torture us for knowledge of the future, to your buddies in the Academy deciding to imprison and torture us for being your accomplices in stealing their magic reserves!"

Zeref and Lucy glared at each other. Then, crossly, the boy folded his arms. "You know, this sort of betrayal is exactly what makes innocent young scholars go evil."

"First of all, _no, it's not._ You'll get over it. You're the one who said that a true scholar shouldn't be dissuaded by minor setbacks. And secondly… I don't think it's supposed to happen, Zeref. You're famous for a lot of things, but inventing time travel isn't one of them – and to be honest, judging by the headaches this one has already given me, spreading awareness of convoluted timelines will not improve the world any. Maybe the reason why no one knows you made a time machine is precisely because Yukino and I didn't go to the Academy with you. It would explain everything."

"Not _quite_ everything…" he voiced doubtfully.

"Yes, it would. I'm sorry, Zeref, but we need to go back to the future straight away. You could even say it has already happened."

"We don't know if that's how time works!"

"Which is precisely why we have to play it safe!"

Their eyes locked again. Lucy stared deep into that shining blackness, that paradoxical light. This was the boy who would grow up to be the most feared man in history, but for now he only nodded and said, "Alright, I'll help you get straight home."

"Thank you," she said, and meant it. At her side, Yukino echoed the words. As she watched the white-and-black-robed boy approach the Eclipse Gate, she resolved to find out just what had happened to crush his creativity and kindness. If any trace of this boy still existed in the future, she would find him, and ask him why the world was so unjust.

While she was thinking, Yukino, whose true curiosity was beginning to peek through her crumbling façade of dispassion, inquired, "What happens if no one opens the Gate from the other side?"

"No idea," Zeref replied promptly.

Lucy gave him a pointed look.

"Don't worry, it's not going to happen," he assured them. "When I open the Gate, it will connect to another point along its timeline when the Gate was or will be opened, determined by a complicated mix of time, magic, chaos theory, the stability of the inter-planar convergence, and most importantly, intent."

"That… all sounds rather uncertain."

"I haven't had time to sit down and calculate the precise form each element takes in the equation yet, alright?" he retorted, affronted. "Still, even if your friends in your own time don't open it, it'll just connect to another time when it opened. Probably a few weeks from now when future-me has found another power source and is running some more tests. It's perfectly safe."

"What if there isn't another time to pair it with, though?" Lucy persisted. "What if the Gate is destroyed after it has been opened an odd number of times?"

"Hmm… interesting question. Let's just say that it's probably best not to let that happen… Don't worry, though. This Gate is going to be open all the time now I know that it works, and it's basically indestructible. That's what happens when you invent your own magic-resistant compound strong enough to withstand the temporal vortex. It's a perfectly reasonable precaution to take, really – unlike _some_ fools, who will happily set up their pointlessly fragile experiments in my _clearly labelled_ blast zone and then blame _me_ for running 'an experiment that endangers the lives of everyone in the building, blah blah blah'-"

"Zeref?"

"Yes?"

"Open the Gate before I strangle you with my bare hands."

"Fiiiiiine."

The boy turned his attention back to the Eclipse Gate. Now that Lucy considered it, it really did look different from the version of the Gate that existed in their time. The size was right, but it was nowhere near as elaborate. The intricate mechanism which only the twelve zodiac keys had been able to unlock was entirely absent. Gold and silver patterns had given the Gate of their age an air appropriate for a palace, and compared to it, this one looked less elegant, less beautiful, unfinished.

Then again, to the boy who had built it, the beauty of its very existence would no doubt put any level of superficial decoration to shame.

Oh, he was infuriating, and she did not envy the professors who had to deal with him on a daily basis, but as she watched him humming to himself as he manipulated the magic of the Eclipse Gate for their sake, she actually thought she was going to miss him a little.

"There we go," he chirped, as a tiny crack of light appeared between the towering doors. At first, it was barely visible, but she knew how bright the space hidden within truly was. Those unadorned doors were a maw opening to unleash the sun it had swallowed.

Yukino began walking towards it, but Lucy found herself hesitating.

"What's wrong?" Zeref asked, head tilted to one side, as if the answer were written sideways along her cheeks. "It's perfectly safe. Probably. I've not tried it yet, but _you_ have, and you made it through just fine."

"It's not that." She shook her head. "It's, uh… thanks for trying to be sympathetic towards Yukino. You really do need to think about when to stop talking, but I appreciate you making the effort to be sympathetic, and for helping us get home."

"That's okay," he shrugged, looking baffled. "I'm not sure why you'd expect me _not_ to feel sorry for her after what happened to her sister, but sure."

 _Because I can't imagine the you who sanctioned Deliora's rampage feeling sorry about anyone,_ she thought. Still, she was careful not to let a trace of that grim sentiment show on her face as she said, "Thanks. Good luck with your research. Try not to do anything too evil in the future."

"I won't, don't worry!" he called back cheerfully.

 _You will,_ she thought morosely, but she couldn't bring herself to say that, either. Instead, with a wave, she turned and followed Yukino into the light.

* * *

Sometimes, Lucy thought, the most successful missions were the ones where nothing changed.

Maybe she and Yukino hadn't defeated another dark guild. Maybe she hadn't won the Grand Magic Games or restored Fairy Tail's reputation. Maybe she was returning home with nothing to show for her adventure; no new magic or ally or treasure or peace treaty.

But as the light merged into the palace courtyard, and she found with some surprise that she'd managed to stay conscious this time; as the drifting shapes that had prised their way through her closed eyelids formed into the solid, temporally fixed, logic-obeying forms of her own dimension – and she let out the breath she had been holding, because this _was_ the present she had left – she thought that maybe, that was for the best.

Maybe the world would have been better if they'd killed Zeref, but she wasn't sure that she _wanted_ a better world. This was the present which contained a guild brought together by tragedy and black magic, building the warmest of families from a collection of broken souls. Yes, danger and dark mages also dwelled here, but they could take them on together – and deliver justice to those who deserved it, not innocent children who had yet to do anything wrong.

No, she had never been so relieved to find that things hadn't changed. Her beloved present was safe.

She could finally, _finally_ let out the breath she had been holding… only to choke on it, as a bright voice piped up from behind her.

"Hey, who built a _palace_ on top of my Gate of Time?"


	2. Present I

_**A/N:** Wow, thank you so much for the amazing response to the first chapter! I'm so grateful to everyone who has reviewed, favourited or followed this fic. It really means a lot to me to know that people are interested in this story! Anyway, as warned, here's where it gets a bit less silly. ~CS_

* * *

 **Time for a Change**

By CrimsonStarbird

* * *

 **-Present I-**

It felt like a very long time since Zeref had last been to Crocus.

Time, like everything else, flowed inconsistently through his life. It came in fits and starts – there were days, awful days, when death hung so thick around him that fearful time could only tiptoe by, one agonizing second after another; and then there were times when his plans unfurled around him, intricate as a glass butterfly's wings and vast enough to stretch their shadows across the globe, and ten years would disappear in a single giant wingbeat.

Objectively, he knew that if he looked at a calendar, it would tell him it had been fourteen years since he had last walked these streets, come to investigate a rumour that the great Gate he had given up on long ago had spat five shooting stars out into the night. Objective measurements meant nothing, however, when the answers he'd found there had sparked his first slip of control in decades; a chance meeting and an accidental death. That had cascaded into seven agonizing years of death and loneliness and more death, culminating in his encounter with Natsu on that island sanctuary that had not proven as safe as was promised…

It had taken another seven years to pick up the pieces.

By the time the stories of Fairy Tail's – of Natsu's – return reached him, his emotional controls were back in place, and stronger than ever before. The feelings that their luckless reunion upon Tenrou Island had invoked were a distant, dying light in the greyest of blizzards. He received news of Natsu's doings with no more interest than he would afford the scandal of a minor celebrity in the newspaper. He could observe the strength of his finest creation without hoping for his own end, or fearing it; without any desire to eliminate or embrace his estranged brother.

Thus he had been content to watch the Grand Magic Games through the eyes of his demon spy, without once experiencing the urge to approach Crocus himself.

Not until tonight.

Ever since the second hand of the clock had ushered them from late evening on the 6th July to early morning on the 7th, he hadn't been able to shake a faint but relentless certainty that he needed to be in Crocus for something.

Zeref rarely wasted time questioning his own actions. It wasn't that he was an impulsive man – far from it, in fact. However, experience had taught him the impossibility of finding any logic in his own decisions. Motives cycled like a year of seasons in a single second; actions which seemed perfectly reasonable at the time proved, with the hindsight granted by a passing half-minute, to have been driven by something incomprehensible, like fondness for the brother he detested or fear of the death he had longed for all this time.

On this night, though, his uncertainty didn't come from having a hundred contradictory explanations at once.

It came from the silence of not having a single one.

He could not recall a single reason for needing to be here. No emotion drove him: not hate, not burning passion, not ambition, not need, not wistful longing, not the next step in some devious plan.

Yet wandering the post-midnight streets of Crocus, with no real aim except avoiding the attention of those out celebrating the end of the Games, was the only thing that had pacified his restlessness a little.

Something was telling him that he needed to be here tonight. Something that made no sense, and offered no explanation, and yet, step by step, drew him onwards through the night.

* * *

"Hey, who built a _palace_ on top of my Gate of Time?"

Those weren't words one would normally associate with feelings of intense dread, but they froze Lucy in place more effectively than any dragon's roar.

Slowly, dreadfully, she turned to see an eight-year-old child in unusually archaic clothing gazing up at the palace spires in awe.

To a Mercurius guard, used to dealing with fascinated tourists from far-flung places, that scene would have been perfectly normal.

Lucy, however, would have taken those hypothetical roaring dragons any day.

"Wait a minute," Zeref mused, oblivious to her utter horror. "Is this _my_ palace?"

"It belongs to the King of Fiore!" Lucy snapped.

"Oh." Then he turned to her, black eyes alight with the reflections of a hundred wondrous lanterns. "Am I the King of Fiore?"

"Of course not!"

"Figures," he said sadly. "I guess four hundred years isn't enough for them to have implemented a technocratic government."

The merits of technocracy, however, barely scraped into the top thousand most important matters in Lucy's mind right now. "What are you _doing_ here?" she shrieked.

Unfazed, the boy's little shoulders bobbed up and down in a shrug. "I invented time travel. I go when and where I please."

Lucy picked him up by the back of his robes and swung him round until he was facing her. "Why did you follow us through the Eclipse Gate?"

"You wouldn't prove to the Academy that I invented time travel, so I had to come to the future myself and find some evidence to take back!" Wriggling in her grip, the boy attempted to take in as much of the unfamiliar cityscape as possible. "I must say, considering that I'm supposed to have destroyed it, the future looks disappointingly intact. Are you _sure_ I was the one responsible? There's no way future-me would have signed off on such a half-baked job."

Over the dangling boy's head, Yukino shot Lucy a wary look, and she groaned inwardly. "Look, kiddo, you've got to go back to your own time."

"Not until I've met future-me! I can't wait to have an actual intelligent conversation for a change-"

"You don't understand," Lucy interrupted, shaking him into silence. "It's far too dangerous for you to be here! If anyone realizes who you are-"

"Ah, you have returned," a voice proclaimed.

Lucy let go of Zeref automatically, spinning round to face Arcadios like he was a charging demon. His armour defied the golden lanterns in favour of reflecting the silver-white of the full moon. There was something ironic about that colour, Lucy thought, as she pushed Zeref behind her and hoped he had the good sense to stay quiet.

"Uh, yes, yes we have," she stammered, glancing at Yukino for help. Yukino – who, both fortunately and unfortunately, no longer considered herself a soldier – gave her a helpless half-smile back.

"Were you successful?" Arcadios pressed. "Have you banished Zeref from this world?"

Lucy pressed her lips together and wondered how she was going to explain that they had in fact _doubled_ the number of Zerefs in the world.

"Well, as it happens…" Yukino began, but she tailed off nervously beneath the Colonel's stern gaze.

Even better, Zeref picked that moment to dash Lucy's hopes that he might have acquired some common sense in the last ten seconds. "Actually, we unanimously agreed that murder is wrong, and that we're not going to do it," he piped up cheerfully. "Not to mention, we still have no idea what the rules of time travel are. And although we definitely need to test them at some point, I don't think killing someone in the past is the best way to go about it. Can you imagine explaining that methodology to a viva panel?"

Lucy facepalmed. Luckily, Arcadios was too busy staring at the boy to process his words. "And who, pray tell, is this?"

"Oh, you've probably heard of me," the boy beamed. "I'm the genius mage and inventor extraordinaire, Z-"

Lucy clamped a hand over his mouth. "He's no one! No one at all! Just a stray child who is going _straight back to the past!"_

"Mmpf!" Zeref protested.

"You brought a child back with you from the past?" Tersely, Arcadios shook his head. "Never mind that. Did you, or did you not, complete the task you were given?"

"We didn't, because it's barbaric, and it shouldn't have taken a child to point that out!" Lucy snapped, losing patience with boy and soldier alike. "What kind of justice system sanctions killing people before they've done anything wrong?"

The Colonel's tone dropped several degrees. "As I explained before, this is a most unorthodox case. We cannot punish him after the fact as he is immortal. In this situation, and this situation only, is it not only acceptable but necessary to use time as our weapon. The kingdom must be protected from Zeref's heinous crimes."

"The kingdom is getting on just fine," Lucy retaliated.

"Tell that to those whose families were wiped out by a demon's rampage!" the knight shot back. "Tell that to all the parents whose children were stolen by the slave cults who served him! Tell that to those who lost their friends to the artefacts of death he created!"

A squeak came from behind Lucy's hand. This was exactly what she had been afraid of. She had to get Zeref back to the past before anything else could go wrong, and for that, she needed a way out of this conversation. Fortunately, there was nothing like a good dose of Fairy Tail to disrupt the voice of authority.

"We're not going through with your plan, and that's final," she told Arcadios, before turning very deliberately to where her guild was gathered. Waving her free hand over her head, she yelled, "Natsu, Erza, everyone! We're back!"

"We're not done here!" Arcadios demanded.

"Yes, we are."

Thankfully, Natsu must have heard her shout, because he jogged straight over, ending the Colonel's attempt to interrogate her. "Hey, Luce! How was the past?"

A sudden shock raced up Lucy's arm. Startled, she let go of Zeref, who immediately became a blur of black and white – a blur which shot across the distance and attached itself to Natsu's waist.

"Oi!" Natsu yelped, hopping from foot to foot in an attempt to dislodge his unusual assailant. "Get off me! Off!"

"Natsu! It's really Natsu!" Delighted giggling floated through the night. "Who's the genius? I'm the genius! Hahaha, I actually did it!"

"Hey," Lucy grumbled. She tugged the back of Zeref's robes, only to find it just as ineffective as Natsu's vigorous shaking. "That's _my_ Natsu. Go get your own."

"No, this is definitely _my_ Natsu," Zeref told her happily.

In fact, _happily_ was an understatement. He had sounded happy when he had spoken about inventing time travel. Now, however, he sounded like he'd invented time travel, mathematically proven its laws, patented three new branches of magic, and been granted a professorship-for-life all in one morning. Lucy didn't know how anyone could feel so much happiness without exploding. Then again, if Zeref kept up this level of squeezing, Natsu probably _would_ explode.

" _Definitely_ my Natsu," he repeated. "I would know him anywhere!"

Lucy stopped short. "Hang on, when you say _your Natsu,_ you don't mean-"

"Absolutely!" the boy beamed. Well, she couldn't see him beaming, as his face was pressed into Natsu's side, but she could hear it in his voice. "This is my little brother!"

A lot of things ran through her mind in that moment, but the only one that seemed to make any sense was the dubious word, "Little?"

"It was an apt description the last time I saw him," Zeref shrugged. "Though, you've got a point…" His grip loosened a little – enough to let him gaze up at a dumbfounded Natsu, but nowhere near enough for said Dragon Slayer to be able to dislodge him. "You're _young._ I thought you said this was X791!"

"It _is_ X791!" Lucy retorted.

The boy stared at her, and then he stared at Natsu, and then he took a horrified step back. "It took me _four hundred years?"_ he shrieked.

"Eh?" Natsu managed.

Grinning, Lucy reached over and patted Zeref on the head. "Better late than never, right? Besides, don't forget, you _also_ invented time travel. Does it really matter how long it took you when you also destroyed the idea of linear time?"

"Hmm… I suppose if you look at it that way, it only really took me a year and a half, since I'm here with him right now… Yes, that's the way to count it." Happiness restored, he sprung forwards and looped his arms around Natsu before the poor man could escape. "Natsuuuuuu!"

"Aww, how sweet!"

"WOULD SOMEONE PLEASE TELL ME WHAT THE HELL IS GOING ON?" Natsu roared.

"No problem," Lucy breezed. "Apparently, you're Zeref's younger brother, who died-"

"Temporarily," Zeref interjected.

"Temporarily, before Zeref brought you back to life," Lucy finished. "Any questions? No, good."

"Like hell I don't have questions! This makes no sense at all!"

Distracted by how cute Zeref looked snuggling up to the hapless Dragon Slayer, she just shrugged. "What's your problem?"

"For one thing, I ain't four hundred years old!"

"I invented time travel!" that muffled voice reminded them.

"Also, are you sure you're not four hundred years old?" Lucy tapped her finger thoughtfully upon her other arm. "It would explain why Freed's over-eighty runes trapped you in the guildhall that time."

"Yeah, but they also trapped Gajeel, so unless you're now gonna tell me he's Zeref's nephew or something-"

"You do realize that would make Gajeel your son, right?"

 _"Ewww!"_

"Ah, nothing says familial love like two brothers drawn together by their shared belief that children are icky," Lucy sniggered. Zeref nodded emphatically.

Poor Natsu glanced from his best friend to the small boy who would not let go of him, and back again. She could tell the exact moment he realized this wasn't some bizarre prank – the moment the fires of outrage fizzled and died, leaving a grey drizzle in their place; as unfamiliar for him to feel as it was for her to see.

"But," he tried, "this has to be some kind of mistake. If I had a brother, I'd know about it, right?"

The boy gazed up at him, wide eyes absorbing the full moon's light. "You don't remember me at all?"

Numbly, Natsu shook his head.

"Oh…"

Spurred to act more than she would ever admit by the boy's lonely word, Lucy volunteered, "You don't remember much about your childhood, though, do you, Natsu? You told me once that everything before you joined Fairy Tail was… what were your exact words? Oh, yeah: one big Igneel-coloured blur."

"When did I say that?" he demanded, and she waved her hand.

"Shortly after I joined the guild. Maybe there was alcohol involved; I think it was during one of our parties. You were sat in a corner of the guildhall going on and on about finding Igneel, so I asked if you had a plan, and you said that you didn't, because you couldn't remember any of the places you'd visited together well enough to actually look for him. You decided you were just going to become as strong as you could until _he_ found _you…_ or something along those lines."

"I dunno… everything from before Gramps found me is really vague, apart from a few flashes of Igneel, but…" Doubtfully, he gazed down at Zeref again, though it did not escape Lucy's notice that he had stopped trying to squirm out of the boy's embrace. "Don't you think I'd remember something this important?"

Lucy doubted he had intended it as a compliment, but Zeref did perk up a little at those words. "Maybe it's a side-effect of being resurrected," he pondered. "It would have been experimental magic when I did it, and to be honest, as far as magical side-effects go, memory loss is really quite tame in light of what I achieved. You forgetting me is a billion times better than you being dead."

"Uh, right," Natsu blinked.

"Though, it does make me wonder what future-me is playing at. You'd think he would have introduced himself when you first awoke, or at least explained the situation to you. Where is he, anyway? If I knew I was coming to the future today, I'd have made sure I was here to greet myself. So why _aren't_ I here?"

"Maybe it's just time being weird again," Lucy shrugged. "Maybe we're in another timeline, where none of this happened in _his_ past."

"Maybe… I sure hope time knows I'm going to study the ever-living daylights out of it the moment I get the chance."

"Shouldn't you have done that _before_ you invented a working time machine?"

"Look, if I could pick and choose when flashes of genius hit me, the world would be a very different place!"

Rolling her eyes at him had become such an automatic gesture by now that if he ever said anything profound, she'd be in trouble. "I'm sure. Still, it's probably for the best that present-you isn't here."

"Why'd you say that?"

"Because… well, you remember the whole thing about a man so evil, there were people who actually thought going back in time to kill him was a good idea?"

The boy eased up on his attempt to hug Natsu back into death in order to give her a curious look. "Yes, and _I_ highlighted the fine line between 'evil' and 'tragically misunderstood genius whose innocent invention of time travel accidentally tore apart the future'."

"The thing is, Zeref… like I said, you're not famous for inventing time travel – and like _you_ said, the present doesn't look much like the product of wrangled spacetime."

"So…?"

"Look, I didn't really want to tell you this, but… in our time, you're famous for having done a lot of awful things to people who have never done anything to you. I know we agreed that Yukino's sister wasn't your fault, but still, in this courtyard alone, there are so many people who have lost loved ones to demons you created or weapons of black magic you designed. And that's not to mention the damage done by dark guilds looking for you, or following the writings you left behind… there are a lot of people who believe the world would be a much better place if you had never existed, and none of them are jealous academic rivals."

The boy had let go of Natsu completely now, staring up at her in horror. "No, that can't be right. I'd never do anything like that. History must have got me mixed up with someone else!"

"I'm so sorry, Zeref…"

"Whoa, whoa," Natsu jumped in. "Are you telling me that this time-travelling kid, who is apparently my older brother, is also the younger version of that weird guy who nearly killed me on Tenrou Island?"

Black eyes creased with concern at his words, but it was Lucy who responded. "Yes, Natsu, that _is_ what we have spent the past five minutes talking about…"

"Well I'm sorry if I was too busy trying to process the whole _having a brother_ thing!" he protested. "So this guy is actually _the_ Zeref? The evil one?"

This time, Lucy didn't even get the chance to respond. There was a sharp intake of breath from behind her, a belated reminder that the world consisted of more than their little family reunion. Half the guild had drawn within earshot – and the worst thing was that Lucy couldn't even tell whose horrified reaction she had heard. It could have been any of them, recalling the Lullaby incident, or Tenrou Island, or any of the tales of terror they'd grown up with.

Dreading the sight of Gray or Erza's faces in the crowd, Lucy turned swiftly away, but there on her other side was Yukino. The Celestial mage was no longer smiling. Her stone mask was back in place, as if the raw emotional lava that had poured forth in her most vulnerable moments had cooled and sealed up the cracks again. Only her and Zeref's shared tragedy had been able to reach the humanity beneath it, and yet she had just been forced to watch as he was reunited with his precious brother in front of her.

Worse of all, though, was Arcadios. The soldier strode forwards like a black knight of the old myths, regardless of the colour of his armour. Each metallic footstep resounded like the knelling of a bell throughout the courtyard. "Black Mage Zeref!" he crowed, with something akin to avarice in his eyes.

The boy glanced at Lucy. "Umm… I think that's me…?"

"At last," the soldier breathed. "You're finally here in front of me, mortal and defenceless…"

Zeref shuffled backwards, pressing up against Natsu – who, for the first time since Lucy had met him, didn't seem to know how to react.

"On behalf of the Kingdom of Fiore, you are hereby charged with the following crimes," Arcadios intoned. "Including, but not limited to, the indirect massacre of one thousand individuals by creating Deliora and sending him to destroy the northern villages, and indefinite other demon-related casualties; the murders of thirty nomadic travellers whose only offence was to stumble upon you in the forest; the slaughter of an entire Rune Knight unit sent to bring you in to stand trial; the development of magical weapons intended to further the spread of death magic-"

"I would never do that!" the boy burst out. "You're wrong! I wouldn't do any of those things, I swear-"

The Colonel overrode him. "And how could the nation forget that awful night fourteen years ago? Not satisfied with merely terrorizing the kingdom, you chose to strike directly at its heart. You broke into the palace. You intercepted Queen Alyse on her evening stroll in this very courtyard. And you murdered her in cold blood!"

"No," Zeref whimpered, trembling. "I wouldn't do that! It must have been an accident-"

The swish of a noble blade cut through his protests. It had only ever been drawn in defence of Arcadios's kingdom – once as a commander on the fields of battle; now as an executioner's blade.

"It's your fault that Princess Hisui had to grow up without a mother," Arcadios hissed. "It's your fault that our nation was deprived of its most beautiful light! Now, the Eclipse Gate has finally delivered you to me. Your innocent appearance may have bewitched Lucy and Yukino, but it will not sway me. Tonight, I will not only end your reign of terror – I will prevent it before it can even begin!"

"STOP!" Lucy shrieked, but this time, she wasn't quick enough. The sword's edge strained towards the thread of life – and clashed against a barrier of metal. A second sword had been drawn to parry the blow, and it rested in the hands of a resolute Yukino.

"You can't do this," she told her former commander, with more determination than she had ever possessed when the executioner's blade had been in _her_ hand. "This isn't right. The boy hasn't done anything wrong."

"Yukino!" Arcadios snarled, pulling back his sword and stopping just short of striking at her again. "Have you forgotten about your sister already? Zeref is responsible for her death!"

"Perhaps," came that steady voice, a volatile lava hardened into assured, basalt conviction. "Perhaps not. There is one thing I know for certain, though, and that is that the child in front of you did not cause Sorano's death. He is kind. Far kinder than you. He understood what it was like for me to have lost my sister, whereas you only twisted my feelings to suit your own goal of vengeance. And above all…"

She offered the frightened boy a tiny smile. "He is finally able to be with his brother again. Knowing how much it would mean to me to be able to see Sorano once more… how can I possibly deny that happiness to someone else?"

"How can you claim he deserves happiness, after everything he's done?" the Colonel howled. "So many people have suffered because of him- Queen Alyse lost her life to his evil!"

"I told you, I wouldn't do that!" Zeref burst out. If Yukino had been set in her decision, then he was frantic, a child's true panic only exaggerated by comparison with her rock-steady certainty. One hand gripped the end of Natsu's scarf like it was a lifeline; the other was wound into a fist at his side. "You're _lying!"_

Arcadios gave a dark chuckle. "I am not. If you had any kind of empathy for those who have lost their families, you would agree that accepting your sentence is the best decision for all humanity."

The boy's lip trembled. He glanced almost involuntarily at Natsu, who still did not know what to make of the boy clinging to his scarf, and then, suddenly, Zeref let go. "No," he declared, looking up at Arcadios. "I don't believe you. I _know_ I wouldn't do something like that. And- I'm going to prove it!"

He ducked under Yukino's outstretched sword and scampered off into the night.

"Stop him!" the Colonel howled.

When no one moved – the palace guards were too far away to act, and Fairy Tail hadn't taken orders from a law enforcement official in living memory – Arcadios broke into a lumbering run himself. Two steps later, Yukino was in his way once again, her sword raised.

"Don't think you'll get away with disobeying your commanding officer!" he snarled.

"I resign," she retorted. "I am grateful to you for taking me in after my guild expelled me, although not as much as I would have been had you not also been after my zodiac keys. I do not think you are an evil man, only a misguided one. I will stand in your way for as long as is necessary for you to see that, just as Lucy stood in mine."

As the white knight's eyes flared in rage, Lucy began tugging Natsu towards one of the courtyard's other exits. "Come on, Natsu," she ordered, once Arcadios was fully occupied with Yukino. "Use that dragon nose of yours and track down your errant brother. We need to find him before he does something stupid, gets himself killed, and erases this whole bloody timeline." _Not to mention, resets you back to being dead,_ she thought, and the one good thing about her heart being in her throat was that those awful words couldn't find a way around it.

"Do you really think he's in that much danger?" Natsu inquired.

"I think I know exactly where he's going," Lucy sighed, picking up the pace. "And if I'm right, he's in far more danger than he knows."

"Why?"

"Because, and I can't believe I'm saying this, being one of the few who has suffered through a full conversation with him… but I have a feeling that no one is going to find past-Zeref more infuriating than present-Zeref will."

* * *

"Hey."

What Zeref had been expecting to find in Crocus on this night, he did not know. He had not cared enough to make guesses. If anything, he had let himself be driven here by that strange impulse mostly so that he could prove it as pointless as every other contradictory desire that plagued him.

Apathy was not often a laudable virtue, but in this case, it had saved him a great deal of wasted effort. Another four hundred years of guessing wouldn't have yielded to him the nature of the sheer impossibility that awaited him in Crocus.

"I like what you've done with the Gate of Time," continued the impossibility, as if unaware of how tenuous its claim to existence was. "I was far more interested in getting it to work than making it look impressive – you'll know that, of course – but I must admit, it looks a lot more like the epoch-defining artefact it is with all that decoration. Not that the word _epoch_ is going to mean much now that we're no longer confined to linear time."

It was impossible, and yet it was right there in front of him. The voice at a shrill pitch his own hadn't reached in centuries. The old-fashioned scholarly robes, the likes of which he hadn't seen on any other human being in nearly as long, even if the coloration was inverted. The way the boy wasn't stood still, but was practically _bouncing_ with anticipation, a habit he remembered breaking as though it was yesterday.

And even if he had somehow managed to avoid encountering a single mirror in the past four hundred years, he could feel the resonance deep in the core of his magic – the strange sensation of completing a jigsaw and finding that there were still several pieces left over, neither duplicates nor erroneous but somehow not belonging in the whole.

His younger self set his hands on his hips crossly. "There's no need to look so surprised. We both know you've had this conversation once already."

Zeref stared, and still the words failed to come to him.

At this, his other self's expression became curious; an emotion so straightforward that it sent an ache of familiarity through him. "Unless you've _not_ had this conversation before. How strange. You know, I'm starting to think that time doesn't even _have_ laws. It just does whatever the hell it feels like."

"What are you _doing_ here?" Zeref demanded, when he found his voice.

Receiving a reproachful look from his eight-year-old self was undoubtedly one of the strangest things that had ever happened to him. "Oh, come on. Like the first thing _you_ did when you invented time travel wasn't exploring the future."

"It wasn't," he said automatically. An image of the first and only time he had opened the Eclipse Gate flashed through his mind, rapidly pushed away before his thoughts could wander to the people he had opened it _for._

"Well, it's a good job I'm doing it, then, isn't it?" the child breezed. "Now that there's two of me, we've got double the chance of finally nailing down the laws of time! Where to start… Oh! How about you teach me some magic you've invented?"

Zeref was certain he had never spoken so much, nor so incomprehensibly, about so little. "Teach you…?"

"Yeah! If you invented some magic in the past, and you teach it to me now, then when I go back to my time I'll already know it so I won't need to invent it again, and then the magic will exist even though _no one_ invented it – let's see if that's possible!"

"Why?" Zeref asked.

"Why?" the other one echoed, puzzled. "To determine what is and isn't possible with time travel, of course!"

"But why?"

This time, the boy did stop talking in order to think this through, although his affronted expression faded as he settled upon a bizarre conclusion. "Look, just because you've determined the laws of temporality already doesn't mean you're not supposed to help me out! This was always going to take two of us. Well, two of _me._ I imagine it would take at least five if you start letting other people into the research team."

Zeref frowned. Nowhere in that eager spiel had there been a valid reason why he should care what the laws of time travel were. The boy, however, had already taken his silence as acceptance, and moved on to the planning stage.

"Oh, I know! Intercontinental teleportation! That's impossible in my time, but it was also right near the top of my to-do list, so you must have cracked it by now! Teach me!"

"No," Zeref said.

"Why not?"

"Because I never invented intercontinental teleportation."

"You mean you _failed?"_

"No, I mean I never tried."

"Why not?"

Why, indeed? Zeref could remember, a very long time ago, coming across the limitations of ordinary teleportation, and being both frustrated and thrilled by them… but he could not think of a reason why he would have felt either of those things, and certainly he did not feel them now. "What would have been the point?"

His other self opened his mouth defiantly – and then a crafty spark jumped into his eyes. Those black eyes were an identical shade to his, but at the same time, for reasons he couldn't quite put his finger on, they were far less recognizable as his own than the child's body or familiar-unfamiliar voice.

"I see," mused his young self. "I shouldn't have asked, should I? By doing so, I must have triggered the paradox, preventing you from learning it so you couldn't teach me and thus preserving causality… But in that case, I can circumvent the paradox by picking magic that you definitely _have_ invented! I wonder how time will respond to that…"

Snapping his fingers, his gaze shot up to meet his older self's in challenge. "You look about, what, fourteen? That's how old you were when you discovered the secret of immortality, right?"

Zeref choked.

Either the boy didn't recognize his horror, or he didn't think it in earnest, because he simply continued, "So, why not teach me that? I'll learn it six years early and see how time reacts-"

The words were still tumbling out of the boy's mouth, but Zeref could no longer hear them. There was a roaring in his ears. Screaming. His heart had stopped, constrained mid-beat by an incoherent rage. The pressure was building – and with it, the white-hot urge to erase the pathetic being who spoke so flippantly of things he didn't understand; who had shattered his stability with a few thoughtless words. The only thing restraining his hand was the one universal rule of time travel, the blatantly obvious truth that _everyone_ knew: don't do anything to endanger your past self, because you might well end up erasing your own existence-

And just like that, the screaming stopped. The chaos in his head switched off. The blizzard of ash slumped to the ground at once, revealing the opportunity he should have seen the moment his past self had appeared in front of him.

His eight-year-old self had not been cursed.

His eight-year-old self was mortal.

If his eight-year-old self died, his present self would simply cease to exist, immortality and all.

His heart thudded. A curl of gaseous death, once despised, now his salvation, appeared around his arm, and he sent it surging towards his younger self without hesitation.

"Whoa!" The boy scrambled aside with the instincts of the young, somehow dodging the rush of death magic. "What are you playing at?"

Instead of answering, Zeref raised his hand and set his cursed magic free once more. The boy sprinted to the end of the street, his hasty footsteps peppered by a string of swear words he definitely wasn't supposed to know as he kept half a pace ahead of the tide of death. He threw himself over the low wall of a public park, taking shelter on the far side.

"You can't kill me!" he protested. There was more indignation than fear in his voice – something that made Zeref both irritated and proud. The contradiction was nothing new to him. He strode on through it.

"Watch me," Zeref said, allowing that hated magic to swarm around him once more. It sucked the colour from the grass below until it was as black and white as he himself.

From his position on the other side of the wall, the boy let out a squeak. "The paradox won't let you! If you kill me, I won't grow up and become you, and then you won't exist to be able to kill me-"

"Oh, is that how time works?" Zeref remarked, amused. "That's funny. Because I don't know if that's true, you see, and if _I_ don't know, you _certainly_ don't."

The boy's gulp was audible.

Pausing briefly to size up the length of wall, Zeref flicked his wrist, and half of it exploded in a storm of blackness not even the moonlight could penetrate. His past self darted out from the other half and sought shelter behind an ancient oak. A gleeful smile twisted Zeref's lips, and the tree was withering, fading, dying before he had even consciously willed it so.

"But even if you _can_ kill me," the boy protested, "you're my future! If I die, you'll disappear!"

"I certainly hope so."

"What the hell is wrong with you?" he shrieked. "First you're not interested in unravelling the mysteries of time, and now you're throwing bloody _death magic_ around like it's Ice Make at a sculpting contest – not to mention that you've had four hundred years and you've not even introduced yourself to Natsu-"

The black wind vanished instantly. Not because it wasn't wanted, but because the single-minded fixation that had brought it so meekly to heel had fractured. A thousand dissonant impulses hung like shards of a shattered mirror before him, distorting the clear way forward he thought he'd found.

"You spoke to Natsu?" he whispered. "You _told_ him?"

"I had to, since you clearly hadn't done it!"

He fell to his knees. The grass bowed and died around him, spreading an inky circle along the ground. "How could I have told him? It would have made it so much harder for him to hate me…"

"Why would you want him to hate you? That doesn't seem very conducive to reforming our family."

"He has to hate me so he can kill me!"

" _Why?"_ screeched the boy.

"That's all this has ever been for! That the only reason why I brought him back to life!"

"No, it's not!"

"No, you're right," Zeref said, looking up with sudden thoughtfulness. "It was a mistake. I have to destroy him, before he becomes strong enough to threaten my own life."

"Natsu would never hurt us! And that's completely different to what you just said-"

"But I don't want to hurt Natsu!" he burst out – shouting, because it was the only way to make himself heard over the blizzard of clashing impulses he had not realized raged purely in his head. "I want him to love me, but he'll never love me! And I can't love him either, so maybe it would be best if he just disappeared… or maybe I should disappear… I don't know any more…"

With his eyes screwed shut, and his hands gripping his head with fervent force, he didn't notice that the boy had come out of hiding until he felt a light touch upon his shoulder. His magical core thrummed in resonance, and the boy pulled his hand back before it could grow too strong, but he didn't back away.

"You're not making any sense," said he. "People are always telling me that I don't make sense, but that's because they're too stupid to keep up. The only person who is definitely smart enough to keep up with me is _me_ , but even I have no idea what you're going on about right now."

"Nothing makes sense," Zeref whispered, clutching at his hair, as if he could draw it like a curtain between himself and the rest of the world. "It hasn't, for four hundred years."

"What _is_ wrong with you?"

It was the second time the boy had said those words, but this time it was a genuine question. The answer was not one Zeref had ever freely given, but that didn't matter, when it was himself he was talking to. "The Curse of Contradiction," he answered.

Those four short words were enough. "That's _real?_ I thought they were just saying that to scare me off!"

"It's real. You have no idea what awaits you… no idea what I have been through." Fingernails raked down his cheeks, leaving raw red marks that immediately turned bone-white again, healed. "I lost everything because of Natsu! It's all his fault! I hate him, hate him, hate him!"

"No, you don't," the boy corrected him. "I know you don't, because you're me, and I could never hate Natsu. It's just the curse making you think that."

"I can feel it!" he spat. "I _know_ it's real!"

"No, listen to me-"

The boy's protests only made Zeref draw away, retreating back into himself. "You know nothing of what it's like to live this way. You have no concept of how much I've lost-"

"What you lost, or what you chose to give up for him?" asked the boy, infuriatingly calm. "Because I remember vowing to do anything to bring him back, and as I see it, that's exactly what you've done."

"I…" He remembered making that same promise, saying those same words, and couldn't for the life of him recall what had driven him to do so. He didn't know. He never knew. It was so much easier just to hate everything, pseudo-logical strands of emotion weaving a safe, steady cage around his uncontrollable magic.

Ripples of resonance vibrated through Zeref's magical core as his younger self rested a hand on his shoulder once more. "But I _do_ know. Natsu's our brother and we love him. It's as simple as that."

At those words, Zeref's hands dropped slowly away from his unmarked cheeks.

The storm in his head fell silent. The contradiction vanished. There was only a single emotion left in his mind.

"See?" his younger self was saying. "It's easy when you stop moping and actually _try._ I bet I can find a way to break this silly curse too-"

Zeref laughed.

It wasn't a pleasant sound. The boy scrambled away from him faster than he had when confronted with death magic, and the sight of it only made him laugh harder.

"Why- why are you doing that?" the boy whispered.

"Why?"

It would be so nice to believe his young self's words were true, wouldn't it? To see the world so naïvely. To know nothing of loss, or fear, or loneliness; to be eight years old again and convinced that he knew everything.

To believe that his personal hell was a _choice_.

To act like positive thinking could make the past four hundred years never have happened.

To be able to throw love around so freely, and never know the consequences.

"Tell me, little me," he began, in a purr that had his other self visibly shivering. "When you told Natsu everything, how did he react? Did he throw his arms around you and accept you as his family?"

"Well… it _was_ mostly me doing the hugging," the boy admitted.

"Did he profess his gratitude for everything you did for him?" Sarcasm dripped like liquid darkness from each word. "Did he return even an ounce of the love you claim to feel for him?"

"Well," he tried, each word requiring a hundred times as much bravery than the one before, "he'd only just found out, and it must have been a lot for him to take in, so…"

"I'll tell you exactly how he reacted. He wanted to know if you were the same Zeref he'd heard stories about. He wanted to know if he was related to the dreaded Black Mage, who was responsible for so much death and hatred in this land. He wondered if being your brother made him complicit in the suffering of his friends. If his own guild would start treating him differently because of his bloodline. If they would ever take his side again, knowing that he lives only through the black magic of a monster-"

"I'm not a monster!" the boy retorted, but the last person from whom he could hide his doubt was he himself.

Zeref let the darkness play over his hands again, watching idly as its tendrils reached hungrily for the moon. "Is that so? They didn't tell you about all the things I've done, then – the things that you will do?"

"Well… I mean, they did, but…"

"But what?"

"None of it was on purpose, was it?" the boy finished lamely. "You didn't mean any of it… you've just been misunderstood… haven't you?"

"Misunderstood?" He rolled the word around his tongue like a dragon savouring a particularly flavoursome human bone. "Tell me, how are you here? Why would anyone from this age bother to connect the Eclipse Gate to your time?"

"Because…"

"There's only one thing they could possibly want from that time: you. Which is to say, a vulnerable version of me. What do you think it means, that so many people are willing to sacrifice everything they know and love for a world where you and I never existed?"

"It means that they don't understand what really happened-"

"No. You're the one who doesn't understand." Streams of shadow continued to rise from his body, evaporating and condensing in enthralling patterns. "I am no fool, little me. Do you think I didn't know what the consequences would be, when I created cruel and violent demons and let them loose into the world? Do you think I felt bad about it, when I took the lives of those who thought to usurp my place in history? Do you think I was unaware of all those who have used my magic, my name, my creations to commit atrocities in this world? I was not. I simply didn't care. Every human being in this world could suffer and die and it would mean nothing to me. They are all worthless."

"I _know_ you don't mean that," the boy protested, shaking. "I know other people can be a bit stupid, and they could never appreciate what we do, but they're not _worthless_ … some of them saved me…"

"That only proves how foolish they are. If they had any sense at all, they'd have ended your life at the first opportunity."

Those mirrored black eyes widened with fright. "I don't want to die!"

"You should. It is far better than what you have ahead of you."

"No…"

And yet it was the elder Zeref who staggered backwards as his own magic lashed out. His voice rose to a shriek; his fingers scrabbled once more at his head. _"I didn't do anything wrong!_ All I wanted was to study new magic – all I wanted was to see my brother again – _why did this happen to me?"_

He screamed again. Black wind ensnared the sound in a vast, rising typhoon, making up for in fury what it shed in beauty. "It's not fair, it's not fair, _it's not fair!_ Why was _everything_ taken from me?"

A shrill voice resounded through the hurricane of despair. "How can you say you have lost everything, when Natsu lives?"

"Because the very magic which brought him back to life also took him away from me!" Zeref howled. "If I love him, he dies; if I hate him, he dies – and none of it matters anyway, because _he_ will never love _me!_ Every atrocity I have committed in an attempt to suppress the curse; every time I could not stop myself from caring and watched it take another hundred lives as the price; every time I could not risk stopping the suffering wrought in my name, lest I make it worse; every one of his friends whose lives were ruined by my ancient mistakes – they will _always_ come between us! It doesn't matter whether Natsu lives or dies, because either way, _I will never get my brother back!"_

There was silence, silence and a howling wind. He willed it to still and it did so with perfect, immediate obedience.

"So," he continued matter-of-factly. "I do not care for a world that does not care for me. I will not feel remorse for killing those who do not comprehend the futility of life. You alone have nothing to fear, little me. You won't have to go through any of that. You get to disappear here and now."

In that frozen moment between life and death, their eyes met in the night. There were a hundred emotions written on the boy's face, and not one in a language Zeref recognized.

The slight shake of his head, though – the defiance they both associated far more with their younger brother than themselves – was something Zeref understood perfectly. His restraint snapped. His accursed magic came loose like a pack of pouncing wolves, seething and snarling through the air. An instant before those ghostly jaws hit home, he felt the flicker of short-range teleportation magic as his prey fled the scene.

That didn't matter. He could still feel the faint vibrations within his magical core. He could find his other self easily enough. He wouldn't let this opportunity to die slip away.

He took a step in pursuit, and stumbled. His legs collapsed beneath him. He had not realized how much he was shaking, hyperventilating; a body that didn't need oxygen was suddenly somehow desperate for it. The moon's silver eye was blurred, and he didn't know if the heavens were wrong or if _he_ was.

He was screaming without knowing why, sobbing without knowing why, terrified that he'd lost everything and terrified that he _hadn't_ ; that he was right and wrong and a million other things he had no name for. They did not whisper doubts into his mind, the contradictions. They came for him all at once and ate him alive.

Torn apart by more conflicting desires than anyone could comprehend, the pitiful, wailing wreck of a man they left behind lay and shivered in the shadows and the dirt.

* * *

In a thunder of steel, the sword was torn from Yukino's hand. She did not turn to watch it spin, sparking, across the courtyard. She did not glance away from Arcadios for a moment. The Colonel was stood triumphantly between her and the Eclipse Gate, which still bore her precious keys in its locks. Without them, she didn't stand a chance against the soldier – but she'd known that from the start, and it hadn't stopped her then, either.

Lucy had called her a mage who took things to extremes, but perhaps it would be more accurate to say that when her mind was made up, nothing could change it.

Nothing short of an empathetic Lucy and an innocent Black Mage, anyway.

But Arcadios was neither of those, and so Yukino raised her chin and stared unflinchingly down the length of his sword.

"Stand aside, Yukino," he growled.

"I will not. Not until you can see that what you are doing is wrong."

"I won't warn you again!"

"Nor I you. You will not lay a finger on the past's Zeref."

"Then," he proclaimed, lifting the sword in both hands, "you leave me with no choice. Since you will not hand over the true culprit, I hereby judge you guilty of aiding and abetting the monster who murdered Queen Alyse. You will face the same punishment as he!"

The enraged Colonel's sword sliced towards her neck – which made it her turn to stare, astonished, as yet another sword parried the blow. The gleaming armour and the unmistakeable hair of Fairy Tail's Erza Scarlet blurred past her as a whirlwind of martial prowess, and half a second later, the situation was reversed again: Arcadios's blade was the one screeching to a halt on the far side of the courtyard, and Erza's was at the soldier's throat.

"That is enough," she declared, and everyone listening believed her.

Everyone except Arcadios, who stammered, "But- but-"

"Give it up," a gruff voice interjected. Startled, Yukino glanced over to see a half-naked ice mage stepping up beside her. "No one is killing anyone here today."

"Why are you siding with Zeref?" the Colonel blustered. "Why you, of all people?"

"I ain't," Gray shrugged. "I'm siding with Lucy and Yukino. Besides, any kid who can stun flame-brain himself into silence is okay in my book."

"Isn't family a wonderful thing?" Erza remarked benevolently.

Arcadios's mad eyes roamed from the guild mages assembling against him to his fallen sword. "So be it," he growled. With a swirl of his tattered cloak, like the transformation of a vampire's cape into a bat's wing, he began sprinting towards the Eclipse Gate.

"No!" Yukino shouted, but that word of denial couldn't erase the golden keys still sitting in the Gate, or the mechanism thrumming with gathered magic.

"You can protect your precious Zeref all you like! I will go back even further! I will find a younger Zeref, and kill him myself!"

"It doesn't work like that!" Yukino yelled. "You _can't_ go back further! That was the first time the Gate ever opened!"

"I'll protect this kingdom myself!" Arcadios crowed. "I will eliminate the greatest threat to our shores! I will give our princess back her mother!"

The thunder of time magic reached its peak. Ignoring Yukino's final cry, the Colonel flung open the Gate to a tidal wave of raw energy. It picked him up, armour and all, and hurled him back across the courtyard.

Yukino watched with wide eyes. She didn't know into which era the Gate had been forced to open – she didn't know if meeting an older Zeref, the Black Mage that history remembered rather than the child it had forgotten, was something any of them wanted – but that wasn't the outcome that worried her the most. The Gate's last opening had been coordinated between past and present. But if there was no one to open it from the other side… well, even the genius boy who saw _everything_ as an opportunity to experiment had been keen to avoid that outcome.

And as the first enormous claw thudded down into the present, Yukino understood why.


	3. Present II

**Time for a Change**

By CrimsonStarbird

* * *

 **-Present II-**

Lucy pointed.

Natsu did not move.

Lucy arched her eyebrows in a way eerily reminiscent of Erza.

Natsu swallowed, but still did not move.

Lucy glowered at her best friend.

Natsu planted his feet firmly into the ground and shook his head.

One might have been forgiven for thinking that Lucy was trying to make Natsu do something _really_ bad, like fight a dragon on his own or explain the whole two-Zerefs fiasco to the king.

"Why not?" Lucy demanded.

"Because it's _weird_ ," Natsu whined.

Of course, this being Natsu, he would no doubt have jumped at the chance to test himself against a dragon, and anyone crazy enough to pick _him_ to convince the king that nothing dangerous and/or timeline-destroying was currently taking place in his courtyard would have no one but themselves to blame for the outcome. The figure Lucy was pointing towards, however – the isolated silhouette of a boy dressed in black and white – was proving too intimidating a task for him.

"I don't even _know_ him," Natsu continued, in a tone of voice he wouldn't have dared employ if Lucy's Erza-impression had been any better. "How am I supposed to-?"

Lucy seized his scarf and yanked him towards her. "You listen to me, Natsu Dragneel," she hissed. "That boy is an innocent child, upset and alone in an age where everyone hates him for things he can't even _imagine_ doing. I don't care if you find it weird or not. He needs you."

Natsu's shoulders slumped. "Alright. I'll try…"

Deep within the palace gardens, the young Zeref sat on the edge of a lifeless fountain. Tall hedges, a masterpiece in green by daylight, formed a black barrier impenetrable to sound by night. Water gleamed like the moon's tears in the bottom of the fountain, swirling in slow circles but lacking the impetus to fling itself heavenward.

As Natsu sat down beside him, the boy glanced up, sniffed, and glanced back down again. Natsu shot Lucy a pleading look. When she failed to provide him with the instructions for immediately fixing this entire situation, he swallowed, and began with as much tact as he would use to open hostilities with a dark guild. "So… are you okay?"

"It's all true, isn't it?" Zeref's voice quavered; a dam that had burst and been hastily patched-up, threatening to spill over into tears again at any moment. "What that soldier said about me. I did all those horrid things."

"Well, yeah," Natsu answered, seeming to realize even as he said it that the awkward truth might have been better as a lie.

Zeref sniffed again. "No wonder everyone hates me. He was right, wasn't he? It would be better if I just disappeared."

For a while, silence was his only answer. Then, unexpectedly, Natsu said, "You smell kinda familiar."

"I- I'm sorry?"

"It's weird. I dunno if I can explain it. You don't smell like anyone I've met before, but at the same time, it's not a _new_ smell. It makes me think of the guildhall, and Lucy's house, even though it's nothing really like them."

"Is… is that a good thing?"

"I think so. Yeah. Yeah, it is. It smells like knowing you can fall asleep and be totally safe, if you get what I mean?"

"No," the boy confessed, giving Natsu an anxious look. "And usually when I don't understand things, it's because someone else has got them wrong…"

Lucy sighed internally, but it was more a force of habit than a true response. It was the first time she had ever seen Zeref look nervous when asserting his own genius, as if he desperately wanted to be proven wrong, and she took pity on him. Moving over to sit on his other side, she explained, "Natsu's a Dragon Slayer."

"Oh!" His eyes widened in realization, and then further still in awe, until even the full moon was envious. "So _that's_ why you can smell intangible sensations like that! That makes much more sense! That's so cool!"

"I guess so," Natsu mumbled, more embarrassed than Lucy had ever seen him before.

"I'm not quite sure what this has to do with my house, though," Lucy added, with a pointed look in his direction.

"Well, when I'm there, it's like my dragon instincts are telling me I'm home, you know? That's kind of what I get when Zeref's around, too…"

Lucy opened her mouth, but after one look at Zeref's expression, she decided that her lecture on precisely what proportion of the rent one must pay before they were allowed to consider her house 'home' could wait.

"So, you're a Dragon Slayer now?" Zeref was saying. "That's awesome. I bet you've been on all sorts of adventures in your life. I've missed so much… and I guess it's too late, now."

The switch from delighted back to despondent was so quick, Lucy felt she must have imagined the boy's spark of happiness. Its fading wasn't so much a cloud passing in front of the moon as the last shovelful of dirt burying him where its light would never again reach.

"You're here now, ain't you?" Natsu demanded.

No trace of a smile touched the boy's face. "I spoke to the other me," he whispered.

"What did he say?"

"He…" The boy's shoulders began to shake. "It was awful. He doesn't care about you at all. He's not interested in researching magic. He did all those terrible things that everyone hates him for. And he… he tried to kill me…"

Lucy and Natsu exchanged baffled glances over his head. "But wouldn't killing his younger self cause him to disappear?" Lucy wondered aloud. "Don't tell me he's siding with Colonel Paradoxes-Are-Fun now?"

"That's what he wanted. He's immortal, so he can't die himself, but he thought that if he killed me, then… then he would die too…" A full-fledged sob burst from his throat, and he flung himself at Natsu, wailing. "I don't want to end up like that!"

This time, Natsu didn't need any prompting to put his arm around the boy. He held tight to the brother he'd never known and let him cry. Maybe he didn't know what to say, but that had never stopped him from _acting_.

"You won't end up like that," Lucy asserted. "It's your life, Zeref. This time, you can make different choices."

"I can't," he sniffed miserably. "It won't make any difference, because of the curse."

"What curse?"

"Future-me is cursed," he whispered into Natsu's side. "It's called the Curse of Contradiction. I thought it was superstition, but it's real… It makes it impossible for him to die, but at the same time, the curse kills everything around him. The only way to make it stop is for him to forget the value of the lives around him, but that just makes him do all those awful things instead…"

"That's horrible," Lucy breathed, reaching out to touch the boy's hand.

"That's not the worst part. It affects his mind, too. He's constantly contradicting himself. He states utterly illogical things as if they're true, and a moment later he has forgotten them completely. It makes him want things I know he doesn't want, and hate people I know he doesn't, until he can't tell what's right or wrong, or why he's here, or… I don't want to be like that!"

Natsu's clothes were muffling his shrill voice, but they could do nothing against its sheer, cutting desperation. "It'll make me do things I don't want to do! If I love someone, it'll make me hate them, and if I don't hate them enough it will go ahead and kill them! I'll hurt people, and create evil magic – and it doesn't matter how much I don't want to do all the things he did, because the more certain I am that they're wrong, the more the curse will make me do them, and then- and then-"

His words broke apart into huge, wracking sobs. Natsu held him comfortingly until he had quietened a little, and then asked, "But if it's a curse, something must have caused it, right? Why don't you find out from Big Zeref what it was, and then make sure you avoid that thing when you go back to your own time?"

The boy gave a short, firm shake of his head and resumed sniffling.

"Why not?" Natsu persisted. "Isn't it worth trying?"

Again, he shook his head, his fists balling tighter around Natsu's scarf, and Lucy understood. "It's Natsu, isn't it?" she whispered. "It's because you brought him back to life."

A tiny, miserable nod.

"Oh," Natsu said, in a voice just as small.

Unwanted visions of life without her best friend competed for dominance in Lucy's mind. Would she still have found her way to Fairy Tail? Would she have survived for so long without his uncanny knack for showing up exactly when she needed him? Where would she be without his optimism and his determination holding their team together; without his broad grin welcoming her home to her adoptive family? He was the most precious thing in her life, and she couldn't give him up for anything.

And when she looked at the weeping boy, who would bear the cost of her happiness in full, she felt her heart breaking.

"You don't- you don't have to." Natsu said the only thing he could possibly say in that situation. "You shouldn't- if it'll make that happen to you, just leave me-"

The boy shook his head fiercely. "I won't!"

"Zeref…" Lucy felt those small fingers tightening around hers, splintering her already-fractured heart.

"I'm scared," he whispered. "I don't want to go back… I don't want to end up like him _…_ "

Gently but firmly, Natsu lifted the boy off him. Zeref reluctantly released his white-knuckled grip and allowed himself to be set back down on the edge of the fountain, although not without fixing his long-lost brother with a tearful look of betrayal.

"Zeref," Natsu said sternly. "I don't know you very well, and I'm sorry I don't remember you, but… I think you're a good person."

The boy swallowed.

"And I think that, somewhere deep inside, the other you is a good person, too."

"You can't know that!"

"Yeah, maybe you're right." Then, unexpectedly, Natsu added, "He cried when I met him, though."

"What…?"

"When I ran into him on Tenrou Island. He cried when he saw me. I didn't know why, but it all makes sense now." Natsu tapped his finger against the stone beneath them, letting the night swallow the sound. "I was angry, because I thought he was trying to kill my friends, but if you're right about the curse then I guess he wasn't meaning to hurt us at all. I think he was upset. And I _know_ he was lonely."

Jumping to his feet abruptly, Natsu spun around to face them both, eyes ablaze with the same fire that had brightened the hearth of his adopted family for so many years. "Isn't there an obvious solution to all this? Why don't we just work together with Big Zeref to find a way to break the curse?"

To their dismay, the boy's gaze slipped back to the floor. "If future-me hasn't found a solution in four hundred years, no solution exists."

"We won't know unless we try-" Natsu argued, but the boy shook his head.

"It didn't take me all that long to solve _death,_ " Zeref pointed out flatly. "If breaking the curse were possible, I'd have done it by now."

"Maybe it's not something you can do on your own," Lucy suggested.

"I managed to invent _time travel_ on my own!"

"Ah, but you didn't."

Zeref put being desolate on hold just for long enough to shoot her an unimpressed look.

"Okay, fine, you did," Lucy sighed. "But still, it wasn't entirely on your own. You weren't the first person to travel through time – Yukino and I were. That's because you didn't create magic that sends someone to another time. What you did was build a door that _connects_ two points in time. You can open the Eclipse Gate as many times as you like from your end, but if no one is there to open it from the _other_ end, what you've actually built yourself is a very expensive art installation in the middle of a field."

"I guess…"

"Sometimes you need to look at these things from a different point of view. That's when having other people to work with helps."

"But explaining the magic to you would take far too long. You probably wouldn't understand it anyway."

"I'm not talking about technical details. I'm talking about the possibility of this being a problem that you – well, the other you – can't solve with his current mindset."

"How so?"

"What if it's not about computing a specific counter-curse, or anything scientific like that?" Lucy hazarded. "What if it's something more lateral? If you were cursed for trying to bring the dead back to life, what if the solution is to kill someone who's supposed to be alive?"

"I can't do that!" Zeref burst out, his eyes wide with horror.

"Won't work anyway," Natsu objected. "From what I heard, Big Zeref killed people intentionally as well as accidentally on Tenrou Island, and it didn't break the curse."

"I'm just thinking out loud," she shrugged. "What if we can turn the contradictory element to our advantage? Like that old logic puzzle about executions."

"The what?" Natsu blinked.

"You know, the riddle where you're going to be executed, but you get the chance to determine your method of execution by making one statement. If the statement is true, you are beheaded, and if it's false, you are hanged. In order to save yourself, you have to say _I will be hanged,_ because if it's true they'll behead you, thus making it false, and if it's false they'll hang you, thus making it true, so the contradiction saves you-"

"But by the time they realize the contradiction, you'll already be dead, so what's the point?" Natsu argued. "Wouldn't you be better off fighting your way out?"

Lucy folded her arms. "Natsu, I appreciate that asking you to solve a logic puzzle is about as effective as asking Igneel to hand-knit a jumper for a mouse, but can't you at least _try_ to keep within the spirit of the brainstorming session?"

"I'm just saying-"

"Stop it!" Zeref shouted, and their argument fell apart immediately. "Please, just stop. I know you're trying to help, but… this kind of methodical thinking is the first thing I would have done. I've been trying to get rid of this curse for four hundred years. You're not going to come up with anything future-me hasn't already considered."

"What, so you're giving up?" Natsu demanded.

"I… I don't know…"

"Natsu," Lucy interrupted, her attention caught by something over his shoulder.

He ignored her, folding his arms and glowering down at the boy. "Because, you know, that sounds way too pathetic to be something any brother of mine would do-"

"Natsu!"

"What? I'm just saying it like it is-"

"No, not that. I'm with you on that." Rolling her eyes, Lucy pointed over his shoulder. "But what's _that?"_

Behind him, dawn was breaking over the palace. Except it was only a little past midnight, and she thought they'd managed to avoid breaking time to the point where the sun was now doing its own thing… and even as she was forced to squint against the brightness that pushed against her very soul, she realized that the light was coming from the city, not the horizon beyond. It was too alien to be a dawn, and yet too familiar to be a freak magical accident.

For the umpteenth time that night – not that periods of time such as 'that night' were so clear-cut for her any more – Lucy felt dread rising from the pit of her stomach.

And into that moment of uncertainty charged the most frightening thing of all: Zeref's shout of outrage. "Hey, who's using the Gate of Time without my permission?"

"You have _got_ to be kidding me," Lucy muttered, although she was too worried about Yukino – and the fabric of reality – for there to be any real venom in her words.

Shading his eyes against the light, Natsu observed, "It wasn't nearly that bright when you went through it, Luce."

"It wasn't? Zeref, what's going on?"

The boy had scrambled to his feet atop the fountain's edge, peering over Natsu's shoulder. "He's right. It's not supposed to do that. I think we might be about to find out what happens when the Gate of Time is opened without anyone on the other end… and I'm not even there to take notes!" Ignoring Lucy's dumbfounded expression, he jumped back down to the ground. "The moment of scientific discovery is vanishing before our eyes! Quick, we've got to get over there!"

"Wait!" Natsu ordered, throwing out his arm to block him. "What's that?"

A silhouette was forming out of the light – a great bulk condensing, claws flashing, wings unfurling, a nightmare spat forth from the vortex of time. A monster tore its way into their world and took to the sky as darkness began gathering in the light once again.

"DRAGONS?" Lucy shrieked. "What kind of dysfunctional time machine have you _built?"_

"I don't know why there are dragons!" Zeref shouted back, just as frantic. "It's a Gate of Time, not a Gate of Apocalyptic Doom! This isn't supposed to happen!"

"Well, get rid of them, then!"

"How?" The light had vanished – someone on the ground had closed the Gate – but they could count seven behemoths in the land and sky: moving mountains, living flame, scales of all colours glittering like cursed treasure in the fading glow. Zeref tore his gaze away from the distant sight to fix Lucy with an expression of pure horror. "You can't just _get rid_ of dragons!"

"Then what are we supposed to do?"

"Hope they're the friendly kind?" Zeref guessed.

On cue, a skyborne dragon opened its mouth, unprovoked, and blasted the palace's outer wall into rubble.

"I don't think they're friendly," Lucy said matter-of-factly.

A small hand locked around her wrist as the boy grabbed both her and Natsu. "Then we've got to get out of here!"

Lucy opened her mouth in protest, but unsurprisingly, Natsu got there first. "What, and abandon the city? Our friends are down there! We've got to fight!"

This only made the boy's grip tighten. "You can't fight dragons! It's impossible!"

"I'm a Dragon Slayer! Fighting dragons is what I do!"

"It doesn't work like that! Dragons are too powerful! You can't kill them, even with Dragon Slayer magic!"

"Then how am I supposed to beat them?"

"You're not! You're supposed to run!"

Angrily, Natsu snapped his hand out of the boy's grip. "I ain't _running,_ " he snarled. "Not when my guild needs me!"

But he hadn't taken more than a step towards the courtyard when the boy bounded forwards and grabbed his scarf. "No! I already lost you to a dragon once! I won't let it happen again!"

At that, Natsu stopped trying to pull away. Slowly, he turned back to the boy, and crouched down so that their eyes were level. "Hey," he said softly, putting his hand on the boy's shoulder. "Don't worry. I'm not gonna die here."

Zeref's lip trembled. "Promise?"

"Promise. I'll be right back."

The boy nodded once, and the moment he relinquished the scarf, Natsu was gone. Zeref stared after him, unblinking, as if the magnetic force of his gaze could pull his brother back to him.

Quietly, Lucy said, "He's right, you know. Natsu won't die again. Do you know why?"

"Why?" Zeref sniffed.

"Because he's got someone to protect," she smiled.

"But that's not how it's supposed to work! _I'm_ the big brother. I'm supposed to be the one protecting _him._ "

"Thanks to all this time travel, I'm not entirely sure which of you counts as the elder brother right now," Lucy sighed.

"Future-me is definitely the oldest," Zeref said sadly. "But he's not going to help, is he? Even though death magic is basically the only thing that can kill a dragon…" Then he frowned. With him, it was less of a lightbulb moment, and more like a light switching off, as he disconnected from the world around him and saw nothing but the puzzle pieces falling into place. "Unless… unless you're right, and it's all about turning the contradiction to our advantage… a different mindset… something he hasn't thought of in four hundred years of trying to break the curse…"

"Zeref, wait!" Lucy shouted, but the boy had already teleported away.

Waves of magic flowed around her, and she sighed. She had no way of tracking him through space. She could only hope that he knew what he was doing… just as she could only hope that the Dragneel brother more inclined towards punching dragons than reasoning with murderous future incarnations of themselves knew what _he_ was doing.

As she ran in the direction of the rampaging dragons, she couldn't help wondering if those two were more alike than they appeared.

* * *

 _The last thing Zeref remembered was splitting pain._

 _That wasn't unusual. He had stopped taking due care a very long time ago. After all, there was little point in expending the effort when his body could recover from any damage almost instantaneously. More unusual was the sight that greeted him as his eyelids flickered open: a woman crouched beside him, her face paled by moonlight and frightful concern._

 _As his mind struggled to pull itself out of the well of pain and unconsciousness, he realized that this was no ordinary stranger. He may have preferred to keep his interactions with society to a minimum, but even he could not fail to recognize the regal features and inimitable jade hair of the Queen of Fiore. As more and more of his surroundings etched themselves in silver upon the blackboard of his awakening mind, the towers of Mercurius, familiar from a hundred books and paintings even though he was sure he had never seen them with his own eyes, came into view around them. This was the courtyard of the royal palace itself. Groaning, he rubbed at his forehead as he sat up, waiting for the phantom pain to realize that his body was whole once again and depart for its own afterlife._

 _"Ah, thank goodness, you're awake!" The warm voice of Queen Alyse, wife of the king and treasure of the whole kingdom, reinforced the peculiarity of his situation. "Are you hurt?"_

 _"No," he answered, and, begrudgingly, the pain subsided._

 _"I'm glad to hear that," she smiled. "You gave me quite a fright, appearing out of the wall like that!"_

 _He glanced over his shoulder to see a garden wall with a hole blasted right through it, and everything fell into place. "Oh, I see. I apologize for the damage." At her quizzical look, he explained, "They always tell you only to teleport to places you are familiar with, in case you end up materializing inside a wall, or worse. As it turns out, you should be equally wary about teleporting to places you haven't been for a while, in case someone has decided to build a palace there."_

 _"Mercurius has stood for almost two hundred years," Queen Alyse pointed out, bemused._

 _"Yes," he said tiredly. "I knew it was here, it just hadn't clicked that 'here' was the exact same place as my Eclipse Gate. It's my fault, I suppose. I shouldn't have left it alone for so long."_

 _Preoccupied with getting to his feet and brushing the rubble from his untorn clothes, Zeref did not notice the queen had pulled away from him until she spoke again, a little colder than before. "So, you are also here about that Gate."_

 _He paused. "Also?"_

 _"There has been at least one attempted break-in every night since it happened. Some were convinced that the shooting stars were a sign of the apocalypse. Others believed that some secret weapon we have been developing underneath the palace accidentally discharged, and came seeking evidence of a conspiracy." She shook her head dismissively. "Which, pray tell, are you?"_

 _"Neither," he said earnestly. "I know what the Eclipse Gate is, because I'm the one who built it. If it has opened, I need to know about it. That's the only reason why I'm here. I need to find them… I need to find Anna. Please."_

 _The frosty mask, honed upon the battlefield of a thousand aristocratic parties, relented a little; she believed him. "I'm afraid she has already gone. She went in search of the children."_

 _His heart jolted. His words tripped over the sudden, unexpected adrenaline, and he stammered, "The- the children – they all came through? All five of them?"_

 _"Yes, there were five. Anna said…"_

 _She was still speaking, but it no longer seemed important._

 _Natsu._

 _Natsu was here._

 _He was going to see Natsu again._

 _A single tear slipped down his cheek, and he didn't know why. There was nothing emotional about the queen's words, let alone sad. It was only the confirmation of a fact he had known to be true since he first heard the rumour of shooting stars – no, since that day four hundred years ago, when he had helped Anna connect the Eclipse Gate to an unknown future. Their plan had worked. In this time, the Dragon Slayers would become strong. Strong enough to end his life. He had waited so long to die, and now, at last-_

 _He was going to see Natsu again._

 _That wasn't the logical destination of that particular train of thought, and yet it ended up there anyway, as inexorable as the tears that would not stop rolling down his cheeks._

 _"Are you sure you're not hurt?" asked Queen Alyse, her voice filled with concern for a stranger, and he nodded wordlessly. He wasn't hurt at all. He was going to see Natsu again, and that thought swept away all trace of physical pain, and more._

 _After all this time, he would be reunited with his little brother. He could talk to him. See how much he'd grown. Find out all the adventures he'd been on with Igneel; tell him about all the things he himself had done while they had been separated by twisted timelines. He would show him the wonders of the modern world – how Natsu had loved it, whenever he'd returned from the Academy with a new magical trinket to show him!_ _–_ _and the nation he had built at its heart._

 _How could he have looked towards this day with nothing but dread and cold logic? How could he have seen Natsu as nothing more than a chance to escape this life? He didn't want to die. He wanted to see Natsu. For so long he had let his life be defined by loneliness and despair, and it was all because he had forgotten this hope; forgotten that no matter how long the centuries of isolation were, there was something worth any amount of waiting-_

 _Oh._

 _Right._

 _That was why he had forgotten._

 _Black wind laughed as it ripped through the courtyard, stealing the light from the moon, the lanterns, the kind queen's eyes._

 _That was why he hadn't been looking forward to being with Natsu again: because he_ couldn't _be with Natsu_ _. Whether they were in the same era or not, they could never be family. He couldn't even talk to his brother. Couldn't show him the world. Couldn't even tell him who he was. Couldn't do anything except wait to die._

 _This wasn't hope. Oh, no. This was the cruellest of torments, to be so close to Natsu after so long, and yet so very far away…_

* * *

A rippling in his magical presence alerted Zeref to the fact that he was no longer alone. Black eyes sharpened as they focussed upon the present version of Mercurius – one that was far more broken than the Mercurius in his memory, for the curse unleashed there had only damaged the living, whereas the dragons rampaging in the here and now were tearing up the city and its palace with frightening ease.

He did not look away from the destruction, or the Dragon Slayers trying futilely to stop it, as the patter of light footsteps stopped beside him. It seemed his foolish younger self was incapable of learning his lesson.

Perhaps the boy realized no acknowledgement was coming, or perhaps his juvenile brain grew tired of waiting, but in the end, he spoke first. "I notice you're not helping."

"Neither are you," Zeref pointed out mildly, watching the swing of a dragon's tail take out a turret and a so-called Dragon Slayer in one go.

"You know full well I don't have any magic capable of defeating dragons yet," his younger self retorted. "You, though – immortality? Death magic? Not even a dragon could survive that combination. You could stop this slaughter any time you wanted."

"Perhaps," he agreed, but he did not move.

"Natsu's down there, you know. Fighting for me. For us."

"Good. Maybe he'll get himself eaten by a dragon, and save me a job."

There was a pause, and then the boy said, "Okay. I thought I'd give you another chance, but I see that there's no point. I only really came here to tell you that I've made up my mind."

"Oh? What about?"

"You," came the steady response. "I'm not going to become like you."

That was an amusing thought. No one could go through what he had and come out the other end unscarred, their hearts untouched by hate – let alone an idealistic child who had made the exact same mistakes once already. "Yes, you will."

"No, I won't. I'm not going to do it, you see."

A frown deepened the shadows upon Zeref's face as he turned for the first time to regard his younger self. The boy had clearly been crying. Heartbreak had left its marks upon his cheeks and red-raw eyes, in a way that it never could upon his own. His body had already returned to its usual state, the curse restoring a perfect human body and removing all traces of humanity in the process.

"Not going to do what?" he asked.

"I'm not going to bring Natsu back to life."

"Yes, you are," Zeref told him.

"No, I'm not. I'll go back to the past, but once I'm there, I'm going to give up my goal of bringing him back. I'll keep researching, of course – more reliable time travel, inter-continental teleportation, all the other things on my to-do list that you've let fall by the wayside – but I'll stop trying to disrupt natural law, and let the dead stay dead. I'll never be cursed like you were. I refuse to lead such a miserable life."

"But…" Perplexed, Zeref shook his head. The words were coming out of his young self's mouth in a perfectly logical order, but they weren't making sense at all. "Then Natsu won't come back to life!"

"I think that's how it's supposed to be. People die all the time. It's a natural part of life… one we all have to accept in the end. That's what your curse has been trying to teach you, and now, through me, you've finally learnt that lesson. We've earnt the right not to be cursed – or, at least, _I_ have."

"But then you'll never see Natsu again!"

"I won't either way." His young self's gaze slipped to the ground, downcast, beaten. "Tonight, he'll die anyway. I can't save him from dragons. They're going to kill him before you have even _introduced_ yourself to him, let alone got to know him. I'm watching my future unfold right now. Even if I do bring him back to life, and in so doing, become _you,_ I'll suffer for another four hundred years – and at the end of it, I still won't have what I want."

"But…"

"It was nice being with him for a while. It really was. But you were right. He doesn't remember me. He certainly doesn't think of me as a brother – and why should he believe we're family, when you've never acted that way towards him? Why would he want to _try,_ after everything you've done?"

With a bitterness he should never have understood so young, the boy reiterated, "You were right. We can never be family. So, if I won't get what I want either way, what does it matter if Natsu lives or stays dead? That's why I'm going to rewrite our history."

Zeref couldn't respond to that. Not with logic. Not with anything but the swirling certainty that this was so, so _wrong;_ a certainty defied words and common sense alike. "You can't!"

"Isn't this exactly what you wanted?" his past self countered.

"…What?"

"You wanted to kill me so that you would disappear. But, for you to disappear, I don't _have_ to die. All I have to do is _not become you._ So that's what I'm going to do. I'll stop trying to interfere with life and death. I won't become cursed. I'll be famous for all the brilliant magic I've invented, rather than infamous for all the horrible things you've done. I'll die of old age, or illness, or in a backfiring experiment – you know, something _normal_. I'll get to be happy, and you, _this_ you, will never have to exist. We both win."

"No!" Zeref found himself shouting.

"Why not?" the boy challenged. "I'll change the past and make it better. How is what you want to do any different?"

Zeref howled, "It should be _my_ decision! I'm the one who had to go through all this! _I'm_ the one who should get to live my life over!"

"No. You've had your chance, and you decided not to care. Now it's my turn."

"You can't even _imagine_ what I've been through for this!"

"I'm sorry about that," his younger self said. "But you've let it change who you – who we – are. Your curse may be partly responsible for that, but you've also lost sight of everything that matters to us, and you've got no one to blame for that but yourself. You are not me, and you're not someone I ever want to be. Therefore, I have nothing to lose by erasing you from the timeline. But don't worry," he added over his shoulder, as he walked calmly away. "You won't be upset for long. Once I reach the Gate, you'll cease to exist."

"You can't!" Zeref screamed. _"You can't do this!"_

"Goodbye, future-me."

And then the Black Mage was alone. He stared at the night, at the moon and the stars, at the dragons too hell-bent on destruction to notice one more human being breaking, at the unjust world still turning no matter how many hopes it crushed within its clockwork. He hated it, because it was too cruel not to hate… but he made no move to prevent his other self from reaching the Gate.

After all, it would be far better if he succeeded.

Better for the world. Better for him. Just let him go, let him change the past, let him erase four centuries of suffering and his own cursed existence, and let him finally rest…

And it wouldn't make a difference, because his past self was right. In this timeline, Zeref Dragneel had died a long time ago. It wasn't an accident that his family name had vanished from history. He had chosen to abandon it; to cut all ties; to run from the past, perhaps to disappear entirely.

Soon, that would finally come to pass. Whether his young self made it to the Eclipse Gate, or whether he was eaten by a dragon along the way, he himself would not have to endure this any longer.

As the last of the intuitive, illogical, inexplicable horror he had felt upon learning of his past self's intentions burned out in the grey wastes of his mind, Zeref watched the city choking beneath an apocalypse of dragons, and waited for oblivion to come to him.

* * *

"Outta the way!"

Lucy threw herself backwards as a vortex of red-violet magic churned up the road along which she had been trying to run. The blast dispersed against the scales of a hulking blue-grey dragon with little effect, although Lucy suspected that it would have had much more of an effect against her unprotected skin, and also that its caster wouldn't have cared all that much if she hadn't got out of the way in time. He certainly hadn't cared enough to hold back his breath attack for another half-second.

 _We must be desperate, if we're relying on help from convicted criminals now,_ Lucy thought resentfully, forgetting that this particular criminal had no trouble hearing her thoughts over the din of battle. Cobra paused his sprint towards the dragon just long enough to throw a rude gesture in her direction. Ironically, though, its only effect was to make her grin as she hurried on her way across the battlefield. She had no idea how he was here, or why, but he was helping them against the dragons, and that gave her hope in the midst of the chaos.

At any other time, she would have stayed to help her former enemy. Right now, she had other things to worry about – namely, the little bundle of black and white which, despite being half her size and having eschewed all forms of practical battle magic in favour of that which threatened the fabric of time and space, was not only still alive, but also managing to stay ahead of her.

Still, if he kept this up, he wouldn't remain alive for long. At least she had a _reason_ for not paying as much attention to the dragons as she should have done. Zeref, however, was scrambling through the combat zone as if it were an adventure playground.

A humongous tail clipped the side of a tower, sending an avalanche of brickwork cascading towards them. Lucy noticed it. Zeref didn't. Her keys may have still been in the Eclipse Gate, but her Fleuve d'étoiles had sprung into her hand of its own accord. A flick of her wrist sent the magical whip flowing out towards the boy, ensnaring and pulling him towards her as it retracted into the hilt. He barely had time to yelp before she snatched him safely out of the sky.

"That was so cool!" he exclaimed, wriggling to the ground.

She had acted without thinking – she would have done the same for anyone – but a faint red tinge touched her cheeks nonetheless. It was nice to be appreciated, for a change. "Thanks, I guess."

"Hmm?" His gaze flicked momentarily to her, and then back to the magical whip in her hand. "Oh, no, not you; your weapon! How does it work? Can I take it apart and find out? I've never seen a magical tool like that before!"

Lucy snatched it away from his grasping hand and rapped him on the head with it. "This isn't the time, kiddo! What are you doing in the middle of the battlefield?"

"Oh! Right! I need to find someone with healing magic!"

"Are you hurt?"

"No, it's not for me, don't worry!"

"Then why do you need a healer?"

"I might not. I don't know. But I don't have any better ideas, so I'm going to find one! Do you know anyone with healing magic?"

"You'll probably want Wendy for that," Lucy responded, bemused. "Last I saw, she was fighting that giant green dragon over the other side of the city…" Fighting, indeed. Wendy had tried reasoning with it, at first, and the cost of her kind heart would have been her life had Laxus not arrived in the nick of time.

"Come on, come on!" Zeref's shout reached her over the din of a city falling apart, which was no mean feat given that he was already two streets away. Lucy hurried after him. Whatever he was planning, she couldn't leave him unsupervised in a war zone.

They didn't get far.

The houses to their right exploded. A wave of fire and force sent them both sprawling. With practised agility, Lucy bounced back to her feet and reached out to help the boy up – only to find a third body lying between them. Natsu.

She almost didn't recognize him. Ash and dirt prematurely aged his sakura-pink hair. Rampant flames had burnt his coat to rags. Trails of blood formed a growing tribal tattoo upon his arm, his shoulder, his chest.

What _really_ made him different to the Natsu she knew, however, was the fact that he didn't get up.

He lay there upon the smoking ground, breath rasping, shoulders struggling, and it was _wrong._ No mortal foe could knock Natsu down, and nothing short of death could keep him there. Not Hades's terrifying magic, not Sabertooth's relentless might, not the best the dark guilds of their age had to offer. Natsu never stopped fighting, not ever.

He wasn't just Fairy Tail's power. He was its inspiration. Fairy Tail won because they never gave up… and _they_ never gave up because _he_ never gave up.

He coughed blood onto the cobblestones beside him and still did not get up, and that was when Lucy realized they weren't going to win.

Up until that point, she hadn't given defeat much thought. She'd known dragons were resistant to magic, and assumed her friends would find a way to break their defences. Yes, Zeref had been so afraid of the dragons that he'd tried to stop Natsu from fighting, but she'd put it down to overprotectiveness towards the brother he'd lost once already. He'd claimed not even Dragon Slayers were strong enough to beat a true dragon, and she had smiled inwardly, because he had never met _their_ Dragon Slayers.

An unstoppable enemy had appeared, and she had just assumed they would overcome it.

They had fought difficult battles before, but always with hope, and always with Natsu's flames as their beacon in the night.

At the end of the street loomed the monster that had doused them. It burned far brighter than her fallen friend, bright with the flames of purgatory, a titanic beast of pure fire in a semi-draconic shape. The stink of brimstone prowled with it; stone softened and warped beneath its claws; its wings seemed to grow and grow as its flames caught and spread through the buildings on either side. The only thing more intense than that cursed fire was the white madness blazing in its eyes.

That beast of hellfire did not belong in their world, and yet it roared with the triumph of the conqueror as it trampled the greatest of human cities. Endlessly it burned, undiminished by the smoke and the dust and the pain that had extinguished her best friend's flames, her hope.

"Natsu!" Zeref shrieked, dashing through the rubble to his brother's side. He tugged at Natsu's arm, trying to pull him back to his feet, though it did little more than provoke a groan from the wounded Dragon Slayer. "Are you alright? Tell me you're alright! Please!"

"I'm alright…" Natsu croaked.

Zeref gave a shaky smile, but those words rammed another nail through Lucy's crucified heart. Natsu wasn't alright. Not at all. But even if he was, and he was only lying down because he was as confident as the hare who napped in the middle of races, it didn't change the fact that his foe was _more_ than alright. The fiery monstrosity advanced with slow confidence, unharmed by the clash that had left Natsu face-down in the dirt.

Natsu was the Fire Dragon Slayer. If he couldn't even scratch the fire dragon, no one could.

And there were six more of them.

And not even Zeref knew how to stop them.

"Come on!" the boy in question was urging Natsu. He had managed to get him to his feet by hoisting one still-bleeding arm over his small shoulders, but that wasn't enough. "I told you, we can't fight them! We've got to run!"

"And I told _you,_ I won't run!" Natsu snarled back. "I won't abandon the city, or my guild!"

Wrenching himself free, he managed a half-step towards his opponent, planting himself firmly between the boy and the dragon. It might have been a defiant act, if those eyes had held any conviction that he was doing more than buying them a few seconds. The monster's mouth opened – a crack in the surface of a fiery planet, revealing the molten core within.

Zeref whimpered, and Lucy knew it had nothing whatsoever to do with his own proximity to death. "Natsu, please," she whispered. "Zeref's right, let's retreat for now, and come up with a strategy-"

She was speaking to empty air. Natsu was already hurtling towards the infernal beast. His magic crackled around his raised fist, the final flame of a candle against a torrent of liquid fire.

Moments before he reached his target, a streak of black lightning shot down from the heavens and connected with the dragon's back.

It did not stop the beast, or slow down its wrath – or, so it seemed, have any effect at all. Yet as Natsu threw himself forwards and the fire dragon lurched to meet him, Lucy could have sworn she saw a figure standing atop the burning dragon's back… a figure dressed in black and white robes. Startled, she glanced down, but the boy was still at her side, his fingers in a vice-like grip around her wrist. But if _their_ Zeref was down here, then the one up there…

Darkness swallowed the fire dragon whole, and just like that, its light was snuffed out.

* * *

It wasn't a lightning-strike epiphany. If it had been, Zeref would never have trusted it. He received those daily, courtesy of good and gracious Ankhseram, so why would that sudden change in his thinking be any more reliable than the urges of his curse?

Instead, it started, as so many things had done back when he was eight years old and the world existed purely for him to study, with a hypothetical question.

 _What would Zeref Dragneel have done in a situation like this?_

It wasn't a genuine question, because if it had an answer, it was inherently unknowable. Zeref Dragneel no longer existed to be asked. He had succumbed to the curse somewhere along the way; his desires and aspirations and very reason for being now lay buried beneath a deluge of feelings that weren't truly his at all.

No, it was a thought experiment: an idle puzzle for him to consider, and perhaps to regret, as he waited to die.

After all, if he truly knew the answer to that question, why would he have stopped acting that way? He hadn't _wanted_ to become a person his own younger self would revile. He hadn't been given a choice. The curse stole his answers away, and left him with naught but madness.

He considered the hypothetical scenario, and decided that the person he had once been wouldn't be particularly happy about this situation.

Somewhere out there, Natsu was about to be killed by a rampaging dragon… and the _first_ time that had happened he had been rather upset, even if the price he had paid for the vow sworn in the ashes of their burning house had since come to show him the foolishness of such feelings. It was more than that, though. The person who had sworn that vow probably wouldn't even have needed the reassurance of death magic and immortality to throw himself between Natsu and a dragon. Wasn't that exactly what he had done back then, only with jealous gods and untested magic as his enemies? He was the kind of fool who wouldn't have realized it would change nothing between them – or wouldn't have cared – and intervened in this situation anyway.

It was a strange way of thinking. Those weren't _his_ feelings. He had extrapolated from the actions of his past, which he could remember but not understand, to reach a conclusion about the present – in short, the 'answer' was nothing more than his best guess.

And that guess meant nothing next to the pure hatred towards Natsu that arose every time he thought about the last four hundred years. The boy was nothing to him. Less than nothing. That was why he had been able to send him away without a second thought- and spent so long waiting for him- waiting to kill him- waiting to be killed by him- waiting, maybe, waiting for some other reason; one that shied away whenever he reached for it, or perhaps he shied from it…

Whimpering, he sank to his knees. The more he tried to reason out how he would once have felt about it, the greater the hollowness inside him grew. His hands clutched at his head, as if to dig out some forgotten vein of common sense with his fingernails. Maybe he loved Natsu. Maybe he didn't. Maybe he wanted to save him. Maybe he wanted him to die.

Maybe it wouldn't matter either way, if the death restrained within him broke free. Maybe he would finally die himself, unnoticed, quietly erased from history by the actions of his younger self, or maybe he wanted to take the whole world with him in one last act of retribution.

He didn't know. He could never know. There was no point trying to figure out the answer, when truth itself bowed to the whims of his curse.

…

Except he had known once, hadn't he?

When the Curse of Contradiction had been a mere folk tale, and life was an exhilarating scramble from one discovery to the next, as heedless to the doubts of others as to their insistences that _this_ was impossible or _that_ was far too complex a research topic for one so young… back then, he had been able to see things clearly.

That version of him, that Zeref Dragneel, had vanished into the depths of history – and been dropped back into his life by a twist of time.

His eight-year-old self had told him that he loved Natsu. That he always had, and always would.

More important than his words, however, was his certainty.

Zeref hadn't been certain of anything in four hundred years. His own feelings were deceitful. He couldn't trust his hatred any more than his love; had no guarantee that tomorrow's desire would further the plans set down today or obliterate them completely.

But he had been certain, once. He had known exactly what he wanted. No risk had been too frightening for him; no setback too great. He would do anything to achieve that goal, and woe betide any universal law that got in his way.

So, if he couldn't trust the feelings of his present self, perhaps he could trust those of his past self.

No, it wasn't a divine epiphany, accompanied by inexplicable innate calm. It was a quiet idea – the kind he would dismiss at first, and then reconsider, and finally wonder if it might contain some small merit after all.

He couldn't force himself to feel a certain way. Even without the curse's interference, he couldn't _make_ himself love Natsu, no matter what his young self said. Nor could he ever become that boy again.

But if he ignored everything his feelings and instincts were telling him, and focussed entirely on his young self's wish… at least then, for the first time in four hundred years, he would be acting not as the Curse of Contradiction dictated, but as Zeref Dragneel should act.

* * *

His world was nothing but fire. Dazzling streaks imprisoned his vision; an inhuman roar filled his ears; his throat spasmed from the smell of his own burning flesh. He could not tell where his senses ended and the pain began.

Yet his arms were healing faster than the fire could burn them. He was as steady as ever, never mind that he was standing on live coals. And when he placed his hands into the infernal flames and called the black wind forth, it came like a hurricane born from the most untameable of seas.

The fire dragon struggled. It didn't want to die. Its flames pushed back against the death magic slowly crushing it, shouting its fear towards the godless heavens with all the efficacy of a man trying to hold back a waterfall with his hands. Like elastic, he felt the exact moment its life was stretched a millimetre too far, and the resulting _snap_ reverberated through his body.

It wasn't regret he felt at the vanishing of its life. Nor was it the grim satisfaction that came from obliterating those who angered him. No, the great beast was dead, the flames that had burnt so voraciously now scattered by that cursed wind, and all he felt was relief.

If it was dead, it couldn't hurt Natsu any more.

Raising his head from the blackened ground, he saw the Dragon Slayer in question through a veil of shadow. The black magic he had invoked had not vanished with the living flame. Still it hungered. It had come at his asking, but would not leave at it, and he knew perfectly well why. He had taken a life to protect one that meant far more to him, and that exchange was not acceptable under the parameters of his curse.

"Oi!" a voice shouted, different to the voice he had never forgotten in four hundred years and yet more familiar than his own. "That was _my_ dragon! Stop stealing my kills!"

He wanted so badly to run over to his brother. He wanted to see Natsu smile at him, to fight alongside him, to make sure he was alright. He would have given anything to be the Heartfilia girl or even his naïve younger self, able to stand at Natsu's side and think nothing of it.

He could never do that.

If he got any closer, the curse would take Natsu's life, too.

But, that didn't matter.

Before the curse could spread further, he twisted on the spot and vanished. He reappeared far from Natsu and his friends – far from _any_ human being, up in the sky the dragons had claimed as their own. Beneath him, a beast of blue-grey scales bleached by the moonlight writhed through the air. Letting himself fall the remaining few feet, he landed with perfect balance at the juncture between its wings. Calmly, because it was the way of the world, he pressed his palms to the rough scales beneath him and told the beast to die.

Black wind swirled over the spines and valleys of its back. Just like the Dragon Slayers' magic before it, it found no cracks there to exploit. Dragon scales provided a perfect defence against magic, so long as they were just that: perfect. A single flaw would give his curse the opening it needed to kill, and the dragon knew it. Its fear shot through him like lightning. It bucked beneath him, forsaking its attempt to raze the Southern Quarter to the ground in favour of ridding itself of this unexpected threat.

Annoyance twanged through his mind as he was forced to cling on. He shouldn't have to do this. He didn't care who lived or died down there. The whole city could vanish, as far as he was concerned – and Natsu with it, for making him be here, for making him act at all, for the crime of _not_ dying before now.

Except he had already decided that he was going to protect Natsu, just like his past self would have wanted. That took precedence over any fickle feelings. Jealousy, hatred, love – they would all pass, and when they did, Natsu would still be his little brother.

He knew the instant the torrent of death pouring out of him found a chink in that armour. The dragon's final breath shuddered free. The strength fled from its wings; they fluttered at awkward angles, buffeted by the wind, as it tumbled from the heavens it had sought to conquer.

His interest in it expired with its life. Before he could fall with it, he pushed away from its back and teleported again.

This time, his foe was waiting for him. He did not even have time to gather his bearings before a tail like a wrecking ball smashed him into the ground and darkness.

The thing was, no one else could do this.

Not Natsu. Not his younger self. Not the Dragon Slayers of this age, not yet. They could rage defiant against their foes until the sun burnt out over their dark eternity, and it would achieve nothing but their own deaths.

He alone could not die.

The moonlit world snapped back into place before his shattered spine had even finished healing. Pain buzzed in the back of his mind, subservient, as always, to his purpose. He was going to protect Natsu. It wasn't some untrustworthy desire, here today and gone tomorrow; it was a cold, hard fact.

He did not bother with anything as mundane as standing. At his silent command the shadows rose up around him, and spat him out into the heavens once more.

Falling again, with the black wind trailing behind him like the wing of an outcast angel, his gaze locked upon the dragon who had failed to kill him, and it stared right back. It had been a long time since he had associated with any dragons, and if he had once been able to read their reptilian expressions as well as those of any human, that skill was now confined to the past. Still, he did not need it to register its shock, or its confusion.

At last, the dragons were starting to understand. The predators-turned-prey dragged their attention away from the pesky Dragon Slayers and to the man beloved of death, who danced seraphic through the sky and brought down humanity's overlords with a single touch.

A roar split the clouds like thunder. Blazing white energy enveloped him. Heat scoured his skin, and then another dragon's breath attack joined the first, and there in the crossfire, his body ruptured from the inside out.

It didn't matter.

His senses shut down, protecting his sanity from the worst of it. All he felt as he drifted through the void of deprivation was impatience. One thousand. Two thousand. Three-

Then he was conscious again, just in time to land on his feet. Ankles shattered to absorb his momentum and immediately reformed from blood and magic. Each breath came thick and fast. He trembled with the fear of his next death and the anticipation of his next kill – or maybe it was the other way round. The only thing he knew for sure was that he felt _powerful._

For so long he had been pushing this away. Now, as he raised his head and stared down mankind's greatest enemy, knowing that _he could not lose,_ the sense of his own power was giddying.

Death – for anyone but him – dived towards him with jaws agape, and he thought about Natsu.

A hundred thousand feelings hit him at once. Fondness, sharp and sudden, as if his heart had become a knife. A lament for the lost little brother who had adored him, whom no resurrection magic could return to him. Bitterness, that the one for whom he had sacrificed everything did not love him, and never would. Loathing, towards the demon who would kill him, and towards himself for twisting his brother's life to that end.

Contradictions that could never be resolved.

And as they threatened to overwhelm him, he thought of the perfect simplicity of his younger self's love. He could never reclaim such a stable, commanding feeling, but he did not need to feel it to be able to act on it. He dismissed every emotion that contradicted it, snapped every thread seeking to bind it, and held the rest close to his heart. It had nothing to do with who he was or how he felt. It was all for who he wanted to be.

"Natsu is my little brother," he spoke, marvelling at how steadfast the words sounded, and how _real_. "It has always been my duty to protect him."

A blast of violet energy churned through the empty houses on either side of him, yet it could not make headway against the black storm that raged in response to his words. He raised his hand and the dragon was swept aside, a sparrow in a hurricane, a candleflame in a rainstorm; it was dead before it hit the ground.

That was not enough for the curse boiling in his veins. If the contradictions could not stop him from protecting those he valued, the curse would drown him in despair. Faster than ever before, and far, far stronger, it surged outward from his body. More and more of the city was plunged into its starless night. The darkness, the hostile cold, the loneliness of the grave – so sang the symphony of the predatory wind; a sudden and vicious reminder that it didn't matter how many people he saved, he could never, ever be one of them. Never to be loved. Forever rejected by the world.

And he smiled.

"So what?"

He teleported back into the sky, taking his curse with him. Death erupted from his body and found not a single human being there to kill. There was a dragon, though, writhing frantically as it tried to outfly the surge of magic. Laughing, he spread his arms wide as he fell back towards the earth.

"Is this supposed to be a punishment?" he shouted to the firmament. "Divine retribution? Is this how you seek to break me?" Flexing his will, he vanished once more and reappeared on the back of the fleeing dragon. "Well, _look at me now!"_

His fists came down with all the momentum of his fall. A single crack in that natural armour was enough. Just one crack, and the ravenous curse reached in and dragged out its soul, leaving its body to tumble wretchedly into the city below.

"It wasn't despair you forced upon me, Ankhseram!" he screamed. "It was power! The power to protect any life I choose!"

Reacting violently to his resolve, the curse expanded further still, and he laughed wildly as he threw himself back into the sky, a safe distance away from everyone. Height gave him the perfect view of the chaos that still raged beneath. Two of the remaining dragons were watching him warily from the still-burning city, but the third was in the wrecked courtyard, bearing down upon an unarmed girl standing defiantly between it and a white-armoured knight.

Yesterday he would have turned a blind eye to the suffering of strangers. Perhaps he would even have encouraged it. Tonight, things were different. To the palace he crashed down like a meteorite, that ancient omen of disaster – right up until the moment the dragon looked up and swallowed him whole.

That was a mistake.

Pain was temporary. Damage would be undone. He could be burned, crushed, dissolved, and it would not stop him. He would take it a hundred times over, as long as it was him alone.

"Natsu is my brother," he vowed. "Natsu's family is my family. I will not let a single person die here today."

All the world's contradictions solidified into a single deafening certainty, and the dragon exploded around him.

Blood and scales rained down upon the courtyard, but he was already gone. Gone, before the curse could snatch the lives of the stunned spectators. Gone to end this threat for good. Gone to fight, like he would have done a long, long time ago, had he realized then what seemed so obvious now.

"I don't need Natsu to love me to be able to love him!" he screamed to the universe. "He is my brother whether he accepts me as his or not!"

It was harder, as he hurled himself towards the sixth monstrous invader, to urge his cursed magic to appear. Never had he pushed it this far before. He had thought it an endless source of despair, but it seemed even divine curses were limited by the growing exhaustion of his body and magic. Although his conviction was stronger than ever, that black wind was weaker; it scattered harmlessly against murky green scales. Annoyance became agony as enormous talons raked across his chest in return.

It wasn't enough to kill him. He staggered but did not fall; kept hold of those few precious seconds death and resurrection would have cost him. As the dragon's cavernous mouth opened, lethal teeth gleaming in the magic building up in its throat, he gritted his teeth against the pain of a wound not yet healed, and drew forth every fond memory that had survived four hundred years of separation.

Natsu's hand clinging tightly to his. Natsu, asleep in his arms. Natsu, curled up beside him as he studied, keeping him warm as the fire burnt low, lifting his spirits with his delight at the illustrations and his unshakeable faith in his big brother…

He did not notice that he was no longer having to sort through a hundred inconsistent emotions to find the ones which matched his resolve; that they were there every time he reached within. He thought only of Natsu, whose life was worth a billion times more than his, and any amount of suffering.

Defiant, proud, he howled, "So what if I can never be with him? If I can't stand beside him, I will watch over him from afar! If he's alive, if he's happy, I don't care if the whole world rejects me!"

A surge of darkness hit the dragon's breath attack head-on. He snarled and his cursed magic spread further – pouring into its throat, bloating its lungs, corrupting its bloodstream, twisting its heart until it ruptured and the dragon fell dead at his feet.

He almost fell with it. With that last outburst, the black wind had all but vanished from his presence. He was tired. So tired. The curse had healed the wound upon his chest, but badly. Knotted skin trailed halfway from his shoulder to his hip – the only scar upon a body that had endured four hundred years of death without change.

Gasping down ragged breaths, he turned to find the last of the present's invaders. The dragon watched him cautiously. A huge, murderous, magic-resistant, terrifying beast, and it was _scared_ of him.

Him, a mortal who had been cursed by a god – and who, in so being, had unintentionally been given power exceeding that of any other living creature.

Another wild laugh forced its way from his lips as he ran towards his final foe.

It wasn't to the dragon he shouted, but to the heavens; to anyone who might or might not have been listening. "You thought to stop me from bringing my brother back to life. Instead, through the curse you forced upon me, you have given me the power to _prevent_ him from dying again! _Natsu – will – live!"_

In a blur of scales and shockwaves, the dragon pounced. Perhaps it felt it had no choice. Perhaps it saw his obvious exhaustion as an opportunity denied to its dead allies. He was too slow to react, and a slash of its arrowhead tail knocked him aside. He bounded to his feet easily enough, but the half-healed gash reopened, soaking the front of his robes with blood.

Good. Maybe the curse would heal it properly this time.

Because, that was the thing. Natsu would live, and so would he. Let the dragons come. A hundred of them, a thousand of them; let Acnologia himself try to take Natsu from him. He was immortal. Death danced at his command. He had nothing to fear from any opponent. He would always be able to protect his brother, and he would always survive to see Natsu again.

"You call this a curse, Ankhseram?" he challenged, laughing as the dragon lunged towards him. Too light-headed to think about dodging, he let a flicker of teleportation carry him aside. Snapping fangs caught him a glancing blow. It was a meaningless gesture, when it would heal again in seconds. "You have given me the greatest gift I could ask for!"

Black sparks fizzled and popped at his fingertips. Twisting, he turned to lash out at its head from close range, but the blast of living night dispersed harmlessly against scales as tough as tectonic plates.

He gritted his teeth. So much for the unstoppable waves of death that his cursed body had been producing mere minutes ago. Emboldened by his failure, one huge claw batted him into the side of a building.

Not dead, oh no, but he was spitting out blood as he got back to his feet. He had never known his immortal body take so long to heal a wound before. It was getting harder to focus as more and more blood pooled at his feet. He tried to imagine Natsu standing behind him, himself the only thing between his brother and his fate, but what should have been a torrent of death born from his desire to protect the most valuable life in his care emerged as a single ghostly shade, so fragile that it was torn apart by moonlight before it even reached the dragon's impenetrable defence.

Not now. He was the great Black Mage, who had not been surpassed in four centuries. Exhaustion would not get the better of him now-

There was a sound like thunder, and something shot past him.

At first, he thought it was an eighth dragon. Its wings were pure fire. Lightning roiled around it like it was the core of a living thunderstorm. But he knew that fearless courage. He knew that magic. He knew the warmth of its owner, even though he had not felt it in four hundred years.

Natsu blazed past him like determination incarnate, striking with the fury of the cataclysm in magic and in flames. Howling in pain, the dragon tried to throw him off – and Natsu let himself be thrown, shouting, "All yours, Zeref!"

 _Thank you, Natsu._

Those words kickstarted his ailing heart. It wasn't the crack Natsu's Dragon Slayer magic had put into the dragon's scales that gave him hope. It wasn't even the sight of his brother alive, or the knowledge that Natsu would be the first to die if he failed now.

It was because Natsu had chosen to put his trust in him.

Maybe it wasn't too late for them after all.

It wouldn't be easy. He knew that, even as he summoned up the last dredges of the nightmare that dwelled within him and let it loose with all the love in his heart. He could never truly spend time with Natsu. He could write to him, though. Maybe even talk to him, if they were careful. He knew now that Natsu would be willing to try. And even if it was too dangerous for him to ever interact with Natsu again, he could follow his exploits in the newspapers, watch over his guild's adventures from afar, and observe him just _being,_ just living the life fate had tried so hard to deny him… and that would be enough.

The last of the invading dragons collapsed dead in the streets of Crocus, and he barely saw it through a haze of tears and dizziness.

He was going to see Natsu again.

The city was growing darker, like stormclouds drawing across the moon.

While he lived and Natsu lived, there was always hope for the future. Thanks to his curse, Natsu had survived the dragons' apocalypse, and he himself was immortal.

Any moment now, the curse would kick in and heal these annoying wounds.

Then he could be with his brother again.

Any moment now.

Any moment…


	4. Future

**Time for a Change**

By CrimsonStarbird

* * *

 **-Future-**

It wasn't the sudden _snap_ Zeref had come to associate with death flinging him back to the mortal realm. Nor was it a normal awakening from sleep – a moment of peace followed by an age of dread, as the dreams dissolved and he was forced to remember who and why he was.

No, it was slow and it was painful, and he didn't want to go. He clung to the darkness and hoped the tiresome tug of life would pass him by.

Far beyond his void-soaked realm, someone was speaking in a shrill voice. "Maybe next time I tell you we need someone with healing magic, you'll actually listen to me!"

"Maybe if you had spent less time screwing with the space-time continuum and more time doing _useful_ research, you could have learnt healing magic yourself," came an unimpressed response.

"It's on my to-do list!" the first voice protested. "Actually, that's an interesting point. You can't use ordinary healing magic on yourself, so I wonder if it's possible to use it on a past or future version of yourself. If I set out to test _that,_ I could research the laws of time travel and learn healing magic at the same time!"

"You know, most people don't have to use hitherto unexplored areas of research as a justification for learning life-saving magic," sighed the second. "They just, you know, do it."

"Ah, but how boring would the world be if I were like _most people?"_ the first countered.

"I don't know, a boring world is sounding pretty good to me right now…"

The serenity of the darkness wasn't coming back, so it was with great reluctance that Zeref gave up waiting and tried to move. At once, the bickering voices cut off. With the instinct of the hunted deer, he sensed more than saw countless pairs of eyes turn to him, sparking palpitations in his heart and a dryness in his throat that not even seven dragons had been able to invoke.

"How are you feeling?" a gentle voice asked.

He opened bleary eyes, and winced as a too-bright world swam into view, populated by a crowd of people uncomfortably close to him. He recognized Natsu at once, watching him uncertainly from the front of the group. His past self was clinging to Natsu's hand, though he seemed – curious? Excited? He couldn't imagine either of those expressions upon his own face, and so he wasn't quite sure how to interpret what he was seeing. The Heartfilia mage's hand rested on his younger self's shoulder. She seemed more worried than excited, just as she ought to be. He was dangerous. Too dangerous.

"Are you in any pain?" the kind voice asked again, and he realized belatedly that he recognized its owner, too. Kneeling beside him was a girl he had met once in passing, four hundred years ago, when she'd been even younger than she was now.

At that, the panic finally became enough to stir his lethargic mind into action. He pushed her away, scrambling back from the crowd, hands flying to his head as if to hold down the lid of some demented jack-in-the-box. "Get away from me!" he tried to shriek; it came out as a scratchy whisper.

"It's alright," Wendy assured him. "It's safe, I promise."

It wasn't. She didn't understand. He shrunk away from her, from all of them, but there were too many well-intentioned strangers and they were far, far too close. Whimpering, he curled into himself and waited, terrified, for the curse to hit. Waited for it to turn his concern for them into derision – or into a slaughter.

Waited, and waited… and waited.

His thoughts remained static, his magic dormant.

He was still waiting when little hands pressed against his own, slowly prying his fingers away from his cheeks. That soft resonance, settling down upon him like a warm blanket, was the only thing stopping him from bolting as his younger self stared searchingly into his eyes. He wondered what this naïve version of himself was hoping to find there. He wondered why he was still bothering to look, when he had already been disappointed once.

On the contrary, the boy was beaming as he stepped away again. "Looks fine to me," he reported over his shoulder, and even more astonishingly, he then turned back to grin at Zeref. "Told you I could find a way to do it."

"Do… what?"

"Break your curse, of course."

Had anyone else said those words, he would have rejected them immediately, but the smugness in them – that enviable _certainty_ – gave him pause. He wondered at the quietness in his head. It was too much to hope for, wasn't it? Too much to hope that the stillness wasn't just the curse lulling him into a false sense of security. Too much to hope that those gathered around him didn't live only because of the confusion of his emotions, but because of some new inability to kill…

"How?" he whispered.

"Simple, really," the boy grinned. "It's the Curse of Contradiction. To get rid of it for good, all you had to do was want to keep it forever."

Zeref stared and didn't understand.

"Well, it only worked because you didn't know it was going to," the boy amended. "You _couldn't_ have realized the answer yourself. If you knew that you were only accepting the curse to make it go away, it wouldn't have truly contradicted itself, and thus working out the solution would have precluded you from ever reaching it… Fortunately for you, you were a genius when you were eight years old too. I figured that if I could get you to accept the curse and all its terrible consequences in return for the power to protect Natsu, it would be forced to destroy itself."

Then, without warning, the boy cupped his hands around his mouth and shouted to the heavens above. "See, Time? _This_ is how you're supposed to deal with paradoxes! Get yourself some consistent laws already so that I can manipulate them in clever ways!"

Lucy flicked him on the forehead.

Still Zeref stared; still he was as silent as the voices in his head. Nothing stirred in the graveyard of contradictions. When a sound finally did escape his lips, it was a plaintive mewl; disbelief and hope and surrender too primal to be put into words.

Then the shadows swirled around him, and the Black Mage fled the scene.

* * *

Eight-year-old Zeref stared at the place where his future self had vanished with his hands on his hips. "Honestly," he reprimanded. "That man has no people skills."

Lucy rolled her eyes. "You're one to talk. I've never seen anyone try to comfort someone else by lauding their _own_ achievements before."

"Well, he _is_ me, so…"

"Where'd he go?" Natsu interrupted, before Lucy could open her mouth again. Which, in retrospect, was probably for the best.

The boy hummed in consideration. "Not far. I can still feel the resonance between our magic. He could be on the other side of the world by now if he wanted to be – well, he couldn't, because he never got round to inventing intercontinental teleportation, but he _could_ be in another city – and he's still hanging around in this one, so he probably doesn't want to be as alone as he thinks he does."

Natsu blinked once. "Why'd he run off, then?"

"Because…" The boy tailed off, looking questioningly at Lucy. When she frowned, puzzled by his actions, he ventured, "I think… I think you might be better at understanding this sort of thing than me."

This time, Lucy couldn't stop herself from smiling. "Well, I can't say for certain, but… I get the impression that this version of you has defined himself by his curse for a very long time. Now that he no longer has that… maybe he doesn't know what he's supposed to do any more."

"So, we need to go tell him!"

"When you say _we…_ " Lucy shot Natsu a pointed glance.

Startled, the Dragon Slayer stepped back, raising his hands as if to ward them off. "Whoa, now hang on a minute. I might have comforted the little one, but I draw the line at doing the big one!"

"Natsu Dragneel," Lucy growled. "You may be the most oblivious human being I have ever met, but I fail to believe that _anyone,_ let alone someone with enhanced hearing and draconic eyesight, could _possibly_ have missed what your brother just did for you-"

"But that's just it!" Natsu protested. "How the heck am I supposed to live up to that?"

"You don't have to live up to anything," Zeref piped up from between them, smiling with that beautiful honesty his older self had long since forgotten. "You just have to… live. That's all we ever wanted for you."

Uncomfortable, Natsu gazed at the ground and said nothing.

"Come on," Lucy urged him gently. "Let's go and see if he'll be more willing to talk when there's no one else around."

At last, Natsu nodded, and the three of them slipped away from the crowd.

* * *

They found him amongst the rubble.

There, in the dust and the dirt, upon ground churned up by one dragon's tail and wiped of life by the breath of another, the Black Mage sat amidst devastation that, for the first time in four hundred years, had not been his doing. Evacuated buildings groaned as they slumped into more comfortable positions. Patches of half-buried embers twinkled along both sides of the street like candles lit in remembrance. At the end of the road, the beautiful view of the palace was blocked by the hulking corpse of a monster, never to wreak its violent madness upon humanity again.

Zeref saw none of this. The city continued to crumble around him, but no tectonic shift could be as monumental as the shift that had occurred for him alone. He stared at his finger – or, more precisely, at the bead of blood growing at the tip of it.

As they approached, Lucy saw him wipe the blood on his robes, and then return to staring as the bead began to swell once more.

"It won't stop," he whispered, perplexed. "It just… it won't stop."

"Honestly," Lucy sighed. Pulling a first aid kit from her bag, she found a plaster and pressed it swiftly across the cut before he could react. "There. I made it stop."

That hunted gaze swept up to her, caught somewhere between apprehension and outright fear.

"I'm Lucy," she added, deciding that even if he knew that already, she might as well be polite. "I take it you know Natsu and, uh, little-you already."

This, at least, had the advantage of turning his unnerving stare to the others instead. Little Zeref had managed to wrangle himself a ride on Natsu's shoulders. He was currently draped across his brother's head like a second black-and-white scarf, and looking rather pleased with himself. By contrast, Natsu's clear apprehension about this entire situation was second only to that of the elder Zeref. His hands twisted around the ends of his scarf.

Before Lucy could speak again, Natsu blurted out, "I'm sorry. For… not being able to remember you. I wish I could." He tried to glance away, but found it too difficult with the extra weight, so he settled for letting his gaze drop instead. "Thanks, I guess."

The younger Zeref hummed happily from his shoulders. The older one continued staring in silence. If anything, he seemed more frightened than before.

"Maybe we could…" Natsu tried again, before tailing off. "Maybe… I dunno, if you wanted…"

Guessing what her usually straightforward friend was struggling to say, Lucy bit back a smile and decided to approach it from another angle. "So, how do you feel?"

"I don't know," Zeref whispered. He pressed his fingertips to his forehead, and then, as if they had not brought the solace he was seeking, drew them slowly away again. "It's so… quiet. I used to feel everything at once, and now… I feel nothing at all. I thought everything would finally become clear when the curse was broken, but I don't know how to act or what to do."

"Well, fortunately for you," past-Zeref piped up, "you've got _me,_ and I've got _loads_ of ideas." Extracting a notebook seemingly from thin air, he dangled it in front of Natsu's face. "Pass this to the other me, please."

Natsu took it, but rather than handing it over, he flipped it open. Curious, Lucy peered in from the side. "What's this?"

"My to-do list. _Our_ to-do list. By all accounts, he's been rather lax when it comes to crossing things off it, but better late than never, right?"

The first two items on the list, _bring Natsu back to life_ and _invent time travel,_ had been crossed through. The remainder was a mix of items Lucy understood _(empirically determine the laws of time; invent an intercontinental teleportation spell)_ and those she wasn't convinced he hadn't made up to make himself look smart _(prove the Lori-Loxley coefficient; find the fifth exception to the Law of Elemental Configuration)._ What really caught her attention, though, was the line squeezed onto the top of the list in still-wet ink: _learn healing magic._

Even that wasn't to remain the most important aim for long, though, as Natsu uncapped the pen and added to the bottom: _go on a Hundred-Year-Quest with Natsu._

Only then did he hand it over, grinning. "How's that?"

Zeref's worried frown did not lessen as he scanned down the list, however. If anything, when he read Natsu's addition, it only deepened into helplessness. "I… I don't even know what that means…"

Back within his area of expertise, Natsu visibly brightened. "It's a really tough mission they only give to the strongest mages! I've _always_ wanted to do one!"

Lucy rolled her eyes. "You know the Master won't let you go on one of those. You're not even S-Class yet."

"Sure he will, if me and Zeref go together! The man just beat seven dragons, Luce! He can take any job he likes!"

"Oh, I see it now. You want Zeref to go on this super-difficult mission with you so that he can do all the hard work and you can take all the credit."

"No, I wanna go on this super-difficult mission so I can prove I'm just as strong as he is!" At her raised eyebrow, he argued, "Look, that thing he did with the dragons was really cool, okay? _I_ want a chance to be that cool!"

"I think it sounds like fun!" the younger Zeref volunteered.

"I don't know…" doubted the other, his whisper a jarring contrast to the boundless enthusiasm of his brother and his younger self. "It doesn't sound like the kind of thing I usually do…"

"Well then, time for a change!" past-Zeref declared.

Lucy gave a deliberate cough. "Putting aside the question of stupidly dangerous missions for a moment – and preferably forever – I think the best thing about that to-do list of yours is that you can research magic from pretty much anywhere. In or around our guild, for example. It'd be good to get to know you better. And to hear some embarrassing stories about Natsu as a baby."

"Oh, we've got _loads_ of those!" young Zeref exclaimed, his eyes alight, right before Natsu clamped a hand over his mouth.

"I'm sure there'll be lots you want to do, once you've had the chance to sit down and think about it," Lucy continued. "Only you can decide who you want to be going forward. It doesn't matter what Natsu thinks, and it doesn't matter what your past self thinks either. You're free to decide for yourself. But, at the same time… if you're looking for ideas, I think sticking with your family might be a good place to start. Natsu and I would be glad to have you around."

Zeref stared at his past self's notebook, and then at his audience, and then back at the notebook. "It doesn't matter what I decide in the end, though, does it?"

"Why not?" his younger self responded.

"Because none of this will happen anyway."

A groan escaped Lucy's lips as she rounded on the boy on Natsu's shoulders. "Okay, how have you screwed up the space-time continuum _this_ time?"

"I don't know!" he protested. "I haven't even touched my time machine since I got here, I swear!"

"Not yet," the older Zeref said flatly. "But once you go back to your own time, this entire present will come undone."

"We don't _know_ that's how time travel works…"

"There's no other way it _can_ work. We can't have a future with Natsu in it if you don't bring him back to life."

"Who says I'm not bringing him back to life?" past-Zeref retorted, offended.

 _"You_ did. When the dragons first invaded."

"Oh, don't worry about that. I was only saying that to get you to think about what Natsu meant to you, and thus trick you into breaking the curse yourself. Obviously I'm going to go back and resurrect him. I'm you, remember? In what universe would either of us ever willingly give him up?"

"But…" Zeref seemed to draw back in on himself, shuddering against the chill of the burnt-out night. "You can't… you can't possibly choose to go back to that…"

"Sure I can. You endured it, therefore I can too."

A frightened breath. "I didn't endure it. Not well… not at all. You don't understand what it's like. You can't… you can't just _accept_ that fate…"

His younger self considered this for a moment. "Natsu, put me down, please." When he was on his own two feet once more, he marched over to his other self, seized the front of his robes, and gave him a vigorous shake. "Has living for four centuries made you senile, or something?" he shouted. "Don't you remember what happened on the day our village burnt down?"

"Of course I do," came the short response, four words containing more emotion than he had displayed in the rest of the battle's aftermath put together.

"We promised to do anything to bring him back," the boy contended. "I don't know about you, but I meant it. _Anything_. Maybe you haven't noticed, but this falls quite neatly into that category. Besides, I can imagine far worse outcomes than this, like the magic taking my life in return for his, because then I'd never get to meet him! At least this way I know it's going to work out okay, in four hundred years or so."

It was Natsu who spoke up next, uncomfortable. "I told you, I don't want you to go through all that because of me…"

"Oh, shush," the boy said, and there was no denying the fondness in his voice. "If not even the laws of magic can stop me, what on earth makes you think _you'll_ be able to? Besides, it doesn't have to be all about you, if you don't want. From what I've heard, a lot of this future you seem quite keen on is dependent on me becoming cursed. Who knows what kind of world you'll end up with if I don't go back?"

Lucy pointed out, "But even if you do go back, the present will change anyway, won't it? There's no way you'll be able to do exactly what the other you did. You know all sorts of things that he didn't – how to break the Curse of Contradiction, for one thing, and you said yourself that knowing the cure would make it fail!"

"Oh, I figured that one out ages ago," past-Zeref replied, waving his hand in a dismissive gesture that immediately erased all the cuteness points he had been racking up in his defence of Natsu's existence. "It's obvious, isn't it?"

"Well, I'm sorry for not being a genius," Lucy snarked.

"You don't have to apologize for that," he shrugged. "Most people aren't. It's just something that those of us who _are_ have to learn to deal with."

After the tension of the apocalyptic battle, it felt so good to just be able to glower at him. The boy didn't share her sentimentality, if the way he gulped and moved swiftly on was any indication. "As it turns out, time travel is far simpler than I thought. The reason why future-me can't remember any of this isn't because of parallel timelines, or anything clever like that. It's because future-me is going to erase those memories from _me_ -me before I go back in time."

"Huh." Lucy mulled this over. "You're right, that _is_ anticlimactic."

If the aghast expression on Natsu's face was any indication, he couldn't have agreed less. "So you won't even know for sure that you'll get to meet me one day? You've got to go through all that not even _knowing-_ "

"First of all, it's the only way to preserve this ending. It'll guarantee that I make the same decisions I did the first time round… and I know it'll work, because it already has," the boy added, nodding towards his older self. "And secondly, I _will_ know for sure, because I'm a genius and I never doubted that I was going to succeed. All I'll forget is how bloody _long_ it took me to achieve it… which, quite frankly, will be a blessing."

"It didn't take as long as you're thinking," objected the older Zeref. Four hundred years had not _quite_ been enough to subdue that part of him. "It's complicated. There's more time travel involved."

"Oh? Tell me! Or… on second thoughts, there's no need, since I won't remember it anyway. I'll figure it out on my own soon enough."

"Your mind is made up, then?"

"Of course." Yawning, as if his decision was so self-evident that no one could possibly refute it, he continued, "I'd best be off, then. Being the first person to travel to the future is fun and all, but to be quite frank, if I want to be attacked by dragons, I can do that in my own time. Besides, where will the future be without my important magical discoveries?"

"Hang on a minute, kiddo," Lucy interrupted.

"What _now?"_

"Well, I might be wrong, since I'm not a _genius_ and all… but my understanding was that the Eclipse Gate needs to be opened from both sides in order to create a path through time."

"Yes. So?"

"Then tell me, O Great Prodigy – when you very sensibly decided to follow us to the present, did you think to send a message asking one of your colleagues to re-open the Gate in a day or so?"

"…Ah."

Natsu blinked. "So, you're stuck here?"

"Umm…"

"Not to mention that the Eclipse Gate is clearly malfunctioning," the older Zeref spoke up quietly. "Where did the dragons come from?"

His younger self winced. "I was hoping you would be able to explain that." The two of them exchanged glances. "I thought it might have been the result of an unpaired opening – a one-off malfunction that drew in the closest living creatures from some random time period, which happened to be murderous dragons from the distant past. But there can only ever be one unpaired opening, which implies that I can't get back home unless someone _does_ happen to open it from the other side…"

"Does it not also imply that the Gate will be destroyed? And yet it still stands."

The boy shrugged helplessly. "There's no time frame on that, though. The Gate was always going to be destroyed – by the passage of time, if nothing else. Besides, there's no reason why there couldn't be more paired openings in the future before the date of its destruction. That doesn't give us any new information."

Zeref thought for a moment, and then suggested, "What if _we_ destroyed the Gate?"

"But- that's my Gate of Time! I spent _ages_ building that! We can't destroy it!"

"We no longer need it. It has served its purpose."

The boy grumbled something unintelligible.

When it seemed that no one else was going to point out the blindingly obvious, Lucy stepped up. "Umm, while I am definitely in favour of destroying the time machine before anyone else has a go at ending human civilization with it, I fail to see how doing so would help you get back to your own time."

"No, Big Me has a point," the younger one mused. "The temporal vortex is highly unstable, which is why it needs to be tethered at both ends for someone to pass through it safely. The physical Gate itself has to be resistant to those forces in order to fix it in place."

Without missing a beat, the other picked up, "If we extracted the resistant component from its magical field and used it to reinforce the path rather than the entrance-"

"The Gate itself would burn out," little Zeref pointed out.

"-but we might be able to stabilize the way for long enough to force it open from this side alone."

"Right," Natsu said weakly, but for the first time, neither of his brothers were looking at him.

The younger asked of the older, "How?"

Flipping to the next blank page of his younger self's notebook without even realizing he was doing it, Zeref said, "We start by reverse-engineering the magical field around the Gate-"

"-project it down the temporal axis-"

"-bounded by the spatial field at the other end-"

"-solve for the invariants-"

"-transform back into real space-"

"-and we can get this to work!" they both exclaimed at the same time. The older one ripped half the remaining papers from the notepad and handed them to his past self. "I'll invert the field."

"I'll calculate the spatiotemporal transformation matrix," the other agreed.

The ruined street was filled with the sound of twin pens scratching on paper, and that was that for a very long time.

Lucy looked at Natsu. Natsu looked at Lucy.

"Umm," Lucy ventured.

There was no response.

She tried again. "Is there anything we can do to help?"

Nothing.

"Should we give 'em some space?" Natsu wondered.

"Honestly, I don't think they'd notice whether we did or not," Lucy sighed. "Are you _sure_ you're related to those two?"

To Lucy's surprise, Natsu was silent for a good while, thinking it over with uncharacteristic consideration. "No," he admitted. "But the more I'm around him, the more I feel it's supposed to be this way. I wanna find out more about my past, Luce. I wanna get to know my brother. Do you think he'll come to Fairy Tail?"

"I don't know." She chose to answer honestly, even though she knew it wasn't what her best friend wanted to hear. "I imagine our guild will be a bit much for him at first, and I'm sure the Council will have something to say about it either way. Still, I expect he'll try and come to Magnolia – and if he doesn't, we'll make sure to visit him a lot. Being around you is probably the best thing for him while he's still figuring out who he wants to be. You're a good influence, Natsu, and I think you're going to be a great brother, too."

His fingers twisted awkwardly in the ends of his scarf, but Lucy didn't miss the way his eyes had brightened, just a little. She knew he was every bit as apprehensive about this new situation as Zeref. It wasn't so much that Natsu hid it better as that it was an entirely alien feeling for him, and she did not quite know how to interpret his subdued demeanour.

Seeing him in that moment, though, Lucy knew he was going to be okay.

And as she glanced over at the two Zerefs, watching as the elder ripped off a page and passed it to the younger with an instruction to check the arithmetic, and it took the younger less than three seconds to circle an error and hand it back (provoking an uttered oath that had even his younger self looking at him reproachfully), both of them working in harmony for the sake of the one person they loved above all else, she had a feeling that _they_ were going to be okay, too.

* * *

Crocus would heal, in time.

Yukino's gaze swept across the battered courtyard walls and fallen palace spires, the lines of smashed windows and melted roofs stretching out like spokes across the city, and it wasn't anguish that crossed her mind, but hope. She had seen the army and the guild mages working together to evacuate the city. She had seen – had _joined_ – the mages who had jumped between Arcadios and the dragons he had accidentally unleashed, never mind that they were the very same mages who had opposed his murderous plan.

Buildings could be rebuilt; the glory of the capital city could be forged anew. Yet the alliances forged amidst that despair, the unity of mages and non-mages, would continue to endure long after all traces of the dragon apocalypse had been banished from the land.

There were some things, though, that could not be so easily healed, and one of them was the Colonel still slumped against the wall behind her.

He wasn't hurt. Not physically, at any rate. He was, however, the only person in the whole city who hadn't understood that the battle was won. Fear haunted his wide-eyed stare. No matter how much his fingers trembled, she had not been able to prise them from the hilt of his sword.

"How could I have done this?" he breathed. "My city… my people…"

"It was an accident," Yukino told him firmly. "We all know that. Not even Zeref knew what would happen when the Eclipse Gate opened again."

"But I was willing to take that risk! I gambled with everyone's lives, and I would have lost them too, if not for… for _him…_ " There were no tears in his eyes, only pain. "All I wanted was for the princess to be able to grow up with her mother…"

Yukino crouched down in front of him, still with the same unhesitant conviction that had first frightened and then reassured Lucy. "Did Princess Hisui know what you were planning?"

"She… she supported the plan to travel back in time and stop Zeref…"

"But she didn't know _why_ you were so desperate to risk everything, did she?"

The veteran soldier could not quite meet her eyes. "No."

"You already knew how she'd feel about that. Instead, you told her it was necessary to protect the entire kingdom, because you knew that was the only way to win her support." His silence told her everything she needed to know, and she exhaled softly. "Princess Hisui is a fine woman, and a wonderful heir to the throne. I have no doubt that Queen Alyse would feel the same. I know that you were only doing what you thought was right, but… if that's the case, then it's not about Hisui at all. It's all about you."

She remembered everything Lucy and the young Zeref had said to her, and she couldn't help smiling. "Think about what those you are trying to help would want – for themselves, for the world, and for you. Princess Hisui is lucky to have a companion and friend as loyal as you. Don't throw that away."

"Perhaps there is some wisdom in your words," the soldier admitted. "I do not know how I can-"

Yukino did not hear the end of Arcadios's doubts, however, as a hand came crashing down on her shoulder. She flinched, reaching first for absent keys, and then an absent sword, and paused only when a voice rang out close to her ear: "Oi, Angel! How'd you get out, huh?"

It wasn't familiarity that relaxed her hand, for she was sure she had never heard that voice before in her life. There was a jovial comradery in it, though – one that assured her she wasn't under attack.

That wasn't enough to stop Arcadios from scrambling to his feet, drawing his sword in one slick motion. "Unhand her at once, you cur!"

The threat was unnecessary. No sooner had Yukino turned to inspect the newcomer than he released her, stepping quickly back. "Sorry," he grunted. "Thought you were someone else."

"That's alright," she said automatically. Sure enough, he appeared far too wild to be any acquaintance of hers. Beneath unruly dark hair, his ears had the familiar points of a Dragon Slayer, while a vertical scar sealed one eye permanently shut. The fur-trimmed coat he wore might have introduced some respectability into his image, if not for the fact that he was also wearing huge, clunky handcuffs. A chain trailed from them to the hands of a nearby Rune Knight, who gave it a deliberate tug, which he ignored.

The stranger frowned as he studied Yukino. "Man, you really do smell alike," he remarked. "Sound it, too. You got a sister, or something?"

Perhaps her polite smile became a little harder to maintain at that, but she answered the query nonetheless. "I had an older sister, but she died a long time ago."

"That's a coincidence. The one I know has a _younger_ sister who died a long time ago."

"What…?"

"Come along, criminal!" the Rune Knight snapped, tugging the chain once more.

"Alright, alright, I'm coming," he muttered. "See you round, Not-Angel."

Despite her best efforts to dismiss the strange encounter, Yukino found herself watching the Dragon Slayer until he was out of sight. It didn't mean anything. It was a simple case of mistaken identity, nothing more. Hers was far from the only broken family in the world. And besides, she knew better than to hope. She had hoped when she first heard of the Tower of Heaven's fall, and it had only made the truth hit ten times as hard. And yet…

She was stronger now. She wouldn't lose sight of the realization she had reached in the past no matter what. And as long as she held onto that, wasn't she allowed to hope, as Zeref had done for four hundred years? Wasn't she allowed to do everything she could? Couldn't she, at the very least, find out who that stranger was, and inquire after his friend?

"Who was that man?" she asked of Arcadios.

The Colonel re-sheathed his sword with a reluctant screech of metal. "Some foul criminal whom the Rune Knights insisted on temporarily releasing in order to help fight the dragons."

Yukino's lips thinned. "Were it not for Lucy's guidance, I would have become a criminal too, tonight. And I am sure you would not hesitate to label Zeref the same way – yet if he had been imprisoned this night, we would both have perished. You ought not to judge someone when you do not know their circumstances."

The soldier dropped his gaze again, conceding her point. "And I suppose I will be the same, after today."

"What do you mean?"

"I intend to turn myself in. I will take full responsibility for the destruction of the city and the harm suffered by its inhabitants."

"Today was an accident," Yukino repeated. "I have no doubt that the King and the citizens will understand that. However, I believe there are two people to whom you must apologize, after the events of today. First of all, Princess Hisui has a right to know what you tried to do."

"I know," the Colonel admitted, with a terse nod. "And the other…?"

"Zeref."

Arcadios's eyes darkened.

She persisted, "While the fact remains that he has done some awful things, there is far more to him than you can imagine, Colonel. I am not asking you to immediately forgive all he has done, only that you listen to him, _truly_ listen, before you cast him out again. Tonight, he saved the city – and perhaps the entire kingdom – from your mistake. For that alone, does he not deserve your consideration?"

"He does," he conceded. "I will shame the Princess no longer. I will apologize for my actions towards his younger self, and allow him the chance to explain himself."

"Good," a new voice piped up cheerfully. "It's quite a long story, though, so it'll have to wait. For now, do you mind if we come through and open the Gate of Time again?"

Yukino froze. Arcadios did the same, with the added effect of looking like someone had slapped him with a wet fish.

Eight-year-old Zeref glanced between them brightly, waiting for a response, and when one had still not materialized three seconds later, he let out a huff. "Yeah, I don't know why I'm asking for permission either. It's _my_ Gate! Plus, I built it here long before you lot went and stuck a palace on top of it!" He shuffled his feet sulkily. "But Lucy said I had to ask permission. And Natsu said I had to do what Lucy said."

"Are- are you sure opening it again is wise?" Arcadios said weakly.

"Oh, don't worry, it'll be perfectly safe. Me and future-me have come up with a way of making it self-destruct!"

For some reason, this did not reassure Arcadios.

"I need to go back to my own time before I accidentally destroy the future. Plus, I've got really important things to do four hundred years ago. If I don't rewrite the laws of life and death, no one else in that moronic Academy is going to do it, that's for sure. So, can we go through? Please?"

Arcadios shot Yukino a helpless look. Stifling a smile – one of many, since she'd met this boy – she gave him a small nod in return. They would offer Zeref their trust, and see what built from there.

"Very well," the Colonel said stiffly. "Do what you need to do. And… good luck."

"Thanks!" the boy chirped.

Yukino and Arcadios watched him dash back across the courtyard to where Lucy and Natsu waited with his other self. The older Zeref hung back from the others. Even at this distance, she could see his reluctance to draw close to anyone; she marked the way his black gaze darted from figure to scattered figure, twitching every time someone moved in his direction. He looked as far as possible from the god of death who had wreaked vengeance upon seven murderous dragons… and further still from the Black Mage who had ruled her nightmares in the years after Sorano was taken.

He had shielded them from the slaughter that day with no expectation that they would accept him because of it. Perhaps it was their turn to see what they could do for him.

"I suppose," Arcadios muttered, "that it might be worth giving him a chance."

"I think so too," she smiled.

* * *

They could have been done with this five minutes ago, but Zeref didn't want to let go of Natsu, and, increasingly, it seemed Natsu didn't want to let go of Zeref either. He had his arms tightly around the boy, and the boy's forehead rested on Natsu's chest, and although neither spoke, and neither moved, it seemed as though they were reciting the world to each other in every breath. Natsu's eyes were closed, but Lucy had been around her Dragon Slayer friend long enough to notice that his nostrils were flared to their fullest extent. She wondered what old memories the scent of his long-lost brother was awakening.

At first, the sight of them together had injected Lucy's heart with helium; now, the growing impatience was pulling it slowly back down to the ground. It didn't help that the Zeref of their time was decidedly _not_ watching the two of them say their farewells. She wanted to say something to him, but she had no idea how to put her sentiment into words without making things worse.

At last, the boy wriggled out of Natsu's arms and gave him a tremulous smile. "I suppose I'll see you in four hundred years, then."

"I guess so. You know, I really think I'm gonna miss you."

"Oh, I'm not _really_ going anywhere," the boy beamed, pointing to where his older self hovered awkwardly. "See? I'm right over there."

"But that version of you is _weird,"_ Natsu whispered.

"Don't worry, I had words with him," the boy whispered back conspiratorially. "Also, he won't tell you this, but he really likes sweet things, so feed him some marshmallows or something if he goes moody on you. And if he hasn't cracked intercontinental teleportation and taken you to Alvarez within six months, tell him off for me."

"Why would we wanna go to Alvarez?"

The boy opened his mouth, then shook his head firmly. "No, I promised I wouldn't spoil the surprise. It's the only way I could get him to tell me what he's been doing all this time. I must say, though, I'm rather looking forward to it at my end. The next four hundred years aren't going to be _all_ bad – I've got some really cool stuff coming up!"

"I- I hope so," Natsu said, ruffling the boy's hair and stepping away. "I'll see you soon, then."

"You will!"

That settled, the boy turned away from his brother and approached his other self. "Let's do this."

"Are you sure this is what you want?" the older Zeref asked.

"Of course." With a wave of his small hand, intended to encapsulate the entire world around him, tangible and emotional, visible and unseen, the boy added, "The present still exists, therefore I have already done it."

"We don't know if time works that way…"

His younger self raised his chin. Enough life for both of them and more sparkled like diamonds in the depths of his eyes. "Well, you'd best get researching it, then, hadn't you?"

The tiniest of smiles touched Zeref's face. "I will." Gently, he raised his hand and pressed it to the boy's forehead. The boy's eyes slid shut. His breathing eased. That was the only warning they got before he collapsed, but it was more than enough warning for Natsu, who was already there, sweeping his brother up in his arms.

"Do you need me to open the Gate?" Lucy inquired.

"No. I will do it myself. I know how, now."

Lucy bit back her question about needing Celestial Spirit magic to open it; past-Zeref had already proven that little piece of knowledge to be an urban legend. Zeref retrieved the golden keys from the door and handed them to her for safekeeping. Then, he placed both his palms against the cool metal and focussed.

Under the pressure of his magic, the air around them first grew warm, and then started to roil with it. A hot breeze buffeted them from more directions than Lucy had thought existed before her own trip through spacetime. Unlike when Zeref had fought the dragons, there was nothing sinister about his presence – nothing dark, from which all the life in her recoiled. Regardless, the sheer magnitude of it was staggering, and the complexity of it doubly so. The Gate's foundations wailed in protest as he rewove the enchantments forged into the metal. What little of the courtyard wall had survived the dragons' rage finally bowed to the pressure of the one who had defeated them, and crumbled into dust.

All of a sudden, the Eclipse Gate's doors flew open. Rather than the blinding, yet comparably tame, light she remembered, the sight before her was a furious whirlpool of colour, writhing with madness and sparking with rage.

"Is it… safe?"

She didn't realize she had spoken out loud until Zeref shot her a half-annoyed, half-patronizing look that wasn't any less irritating on the face of a pseudo-fourteen-year-old than it was on a genuine child.

"Yes," said he. "But it will not remain so for long. Single-tethered vortices are highly unstable."

As if to prove his point, one side of the Eclipse Gate began to warp inwards. Lucy had never seen metal bubble like that before. Especially not magic-resistant titanium compounds. Still, Zeref strode forwards without hesitation and vanished into the magical storm, with Natsu close behind, and so – trying hard not to think about whether being part of a genius mage's temporal experiment was more or less dangerous than fighting seven dragons – she followed.

Wild magic sparked around her. Pain flashed from one side of her body to the other like it was caught in a demented ping-pong relay. Doing her best to ignore the way the ethereal vortex shuddered at her every step, she hurried after the others, and she had never been more relieved to see a boring old field in her life.

They emerged into same pastoral scene she remembered: the simple meadow, the city in the distance, and the world-changing, anomalous, defiant set of doors. This time, they remained open, revealing the agitated vortex within. If they closed, they wouldn't open again into her time… but Natsu clearly trusted that Zeref wouldn't let that happen, so she decided she would too. And if she happened to loiter within touching distance of the portal as Natsu followed Zeref out into the field proper… well, she could pass that off as generously giving the brothers some space.

"Set the other me down here," Zeref instructed. "We don't have much time."

Natsu complied, laying the unconscious form of his brother down in the grass with only a touch of reluctance. That should have been the end of it, but Zeref, without explanation, then drew upon his magic and began burning long, black marks into the field in an explosive arcane pattern.

"What are you doing?" Natsu wondered.

"I remember this," Zeref said, frowning in concentration. "I remember what I saw when I woke up from this. I know what I need to do next."

"Right. And… what _is_ it that you need to do, exactly?"

"Fix the results of the experiment."

Natsu folded his arms. "Look, I get that you're probably not used to having anyone but yourself to talk to, but I'm not a genius of magic, so you're gonna have to slow things down a bit."

Lucy could have sworn there was a smile on the Black Mage's face as he finished scarring the field and moved on to altering the traces of magic in the air around them. "I am reproducing the conditions that would have occurred had my younger self's attempt to open the Eclipse Gate been a failure. Since he will not recall anything that happened, he will deduce, as I did, that the magic is incomplete. Or, more specifically, he will believe that it requires a further component to stabilize the temporal gateway."

"Celestial Spirit magic," Lucy realized.

"Correct."

"Oi," Natsu grumbled, punching her arm lightly. "Stop keeping up with him. You're making me look bad."

Rolling her eyes, she reflected, "You know, ever since Arcadios told me he needed me for the Eclipse Gate plan, I've been wondering what Celestial Spirit magic has to do with time travel. And it turns out, nothing whatsoever."

"Quite so," Zeref agreed. "I had never even heard of Celestial Spirit magic before my analysis of the results of this experiment led me to it. By the time I next opened the Gate, I was convinced that the zodiac keys were stabilizing the spacetime portal for me, when in truth they were entirely unnecessary to the proper functioning of the Gate."

"So, in short, Yukino and I were dragged into this mess for nothing," Lucy huffed.

If it had been the younger Zeref, she was sure he would have brushed it off as all having worked out in the end, or given some smug response about everything being pre-determined by time. This _wasn't_ him, though, and although the physical similarities were clear, there was a full four hundred years of estrangement between them. It was those years that spoke as he dropped his gaze to the ground and murmured, "I guess so…"

Before she could work out how to take back her words – she had only spoken in jest, and she _certainly_ hadn't meant for him to take it personally – Natsu clapped her cheerfully on the back. "Nah, Lucy's magic was definitely the right choice!"

"I think so too," Zeref agreed softly. "I do not think many other people would have given my past self the benefit of the doubt."

Surprise flittered across Natsu's features for a moment, quickly schooled into a serious expression that fooled no one. "Yeah. Yeah, that's exactly why. Definitely."

Lucy sighed. "What were you _going_ to say, Natsu?"

"Well, let's face it, it _is_ usually you who gets landed in this kind of mess, isn't it?"

"Because you always land me in it!" Lucy exploded, as visions of Mr Cursey and creepy dukes and maid outfits and just about every misadventure she had ever been on since teaming up with the enthusiastic Dragon Slayer flashed before her eyes. "And now there's _two_ Dragneels doing it… can I just quit now?"

As Natsu sniggered at her despair, Zeref gave her an apologetic smile. "Not really… after all, this has already happened."

"Yeah, that sounds about right," she muttered, before a thought occurred to her. "Hang on, though. If you only know how to fudge the results of your experiment because you've already seen it done before… then how did you do it in the first place?"

"Good question," Zeref said. "I'll add it to my list."

Lucy folded her arms. "You know, the more I think about it, the more certain I am that time is screwing with us. Or, more specifically, with me. I mean, everyone else is doing it, so why should the space-time continuum miss out on all the fun?"

"Quite possibly," he agreed. "Still, I wouldn't think too hard about it, if I were you."

"Why? Because drawing attention to the paradox might cause the whole timeline to unravel?"

"No, not at all. If anything, I think we've proven that the timeline is rather stable against change, if indeed it can be changed at all. However, I have repeatedly been assured that unravelling the mysteries of time is _my_ job, and I don't think my younger self would forgive me if I let you get there first."

Lucy laughed. "It's all yours, my friend."

"Is that what you're going to do next, then?" Natsu inquired. His voice sounded almost normal. Almost _._ Lucy knew him well enough to notice the buried disappointment, but she realized with a jolt that Zeref probably didn't.

"I think so," he was answering. "I owe it to my younger self… and besides, it _does_ sound interesting."

Natsu tried a smile. "Oh, okay. That's good… it does seem like the kind of thing you'd enjoy, so…"

"Then again," Zeref continued thoughtfully, as if he hadn't heard his brother's words. "That kind of research will likely involve travelling to ancient libraries in exotic, abandoned and very dangerous places, and since I am no longer immortal, I suspect I will have to look for a guild mage or two to accompany me…"

"Hmm." Natsu gave him a suspicious look. "I don't suppose we're talking a Hundred-Year-Quest level of danger, are we?"

"I daresay I could find one that is," Zeref smiled.

"Then count me in!" Without warning, Natsu slung his arm around his brother's shoulders, pulling him into a half-hug. Just like Natsu had when hugged by Zeref's past-self, Zeref tensed completely at first, and then, gradually, like he was awakening from a four-century slumber, he began to relax into it.

"Hear that, Luce?" Natsu crowed. "We're going on an adventure with my brother!"

That was when she knew she had been worrying for nothing. They were going to be fine together. Absolutely fine.

Thanks only to several months of practice, she managed to keep her expression stern. "Well, perhaps our first adventure could be to get back through the violent and unstable portal he made before we're all permanently stuck in the past, hmm?"

"Good plan," Natsu breezed, hurrying for the portal. "Come on, Zeref! Soon as we get back, I'm gonna show you my house! The spare room's all yours!"

Zeref set off after him, but stopped in front of the crackling vortex. As his brother vanished back through time, he reflected, "It won't be as simple as he thinks, will it?"

"No," Lucy confirmed. "I doubt that the Magic Council will be happy to let you walk away and start a new life as easily as that. And, for those who didn't see you save the city, it will take a long time for their opinions of you to change. I imagine we will all face a lot of opposition going forwards."

Zeref's gaze drifted to the city on the horizon. "Perhaps I should stay in the past. I could move to another country – one I know my past self will never visit. I could find a small village there and settle down, living quietly in a place where no one knows me…"

"You could," Lucy agreed steadily. "But, you won't."

"What makes you say that?"

"I might not know you very well, but I do know Natsu, and what's more, I know your younger self too. And neither of those would _ever_ let the opinions of others come between them and the things they love." Shrugging, she gave him an honest smile. "I think it's a Dragneel thing."

"Maybe so." He, too, was smiling as he turned back towards the portal. "Thank you." Then he stepped forward and vanished.

It would be, Lucy thought, a long time before Zeref would be able to accept that the Curse of Contradiction could no longer hurt him. It would be longer still before she could see any more than a sliver of that boy inside him – the boy who had been precocious, audacious, brilliant, and so, so kind.

Maybe he wouldn't need her help to adjust to the new life he chose; maybe Natsu wouldn't need it to accept his brother into his life. She would be there for them either way. Natsu's family was her family, through the guild's unspoken laws if nothing else. And hell if she wasn't going to miss that little brat of a Black Mage too.

In truth, she was looking forward to getting to know her best friend's brother. It didn't matter to her how difficult it might be to convince the world that he wasn't the villain everyone believed – and more importantly, it didn't matter to Natsu either. She knew how hard he would fight for his family, whether his adopted guild or his blood brother.

Zeref couldn't have asked for a better brother. He had done so much for Natsu – and by extension, for her. It was time for them to start paying him back, one Hundred-Year-Quest at a time.

Smiling to herself, Lucy stepped into the imploding portal for the final time, heading for the present… and from there, the future.

* * *

It wasn't waking up to the smell of burnt grass invading his nostrils that bothered Zeref the most.

It wasn't the dull ache in his muscles, drowned out by the march of an enthusiastic one-man band across the stage of his forehead, as he tried to sit up.

It wasn't even the fact that he had regained consciousness lying face-down in a field with no clear memory of what had happened – a rite of passage which most people his age wouldn't get to experience for another ten years.

No, what bothered Zeref was the fact that this was the same field he had passed out in. On the same plane of existence. On the same afternoon. And there was still only one of him in the world.

"I _failed?"_ he screeched, scrambling to his feet in horror. The Gate of Time sat innocently in the field: closed, harmless, and decidedly not connecting his age with any other. He glared at it, as if that miracle of genius and invention had been responsible for miscalculated mathematics, miscast magic.

"I failed," he scowled, folding his arms and sinking to the ground in a huff.

Thirty seconds went by in sulky silence.

Then a minute.

Then he could bear it no longer, and he bounced back to his feet, eyes sparking with a surge of electric ideas. "Was there not enough power? Was the vortex unstable? Did some twisted paradox of time prevent tomorrow's me from opening the Gate at his end? Was there an error in my assumption of spacetime's dimensional quantities? Maybe time doesn't have four-fold symmetry after all. Maybe another element must be incorporated to make it four-fold-" The rapid-fire bombardment of suggestions gave way to a sudden intake of breath. "The magical trace! I need to record the magical trace! Who knows how long I was unconscious for – it might already have faded – _where is my notebook?"_

When the frantic patting of hidden pockets failed to turn up his trusty experimental notebook, the boy proceeded to turn them out one by one, still to no avail. "No, no, no! My experimental data! My research notes! My-"

A single piece of paper fluttered to the ground from one of his pockets. Frowning, he picked it up. The handwriting was not his own. In fact, the messy scrawl was as far as possible from his own meticulously neat notes, and it would be another four hundred years before he saw the two scripts side by side, working together to revive a once-neglected to-do list.

"Crocus, 7th July, X791?" he read, puzzled. "What's that supposed to… mean…?"

If the sentence started as a defiant rejection, it ended as a thoughtful question. His gaze flicked to the faulty Gate of Time, whose silent silhouette gave nothing away, and then back to the paper, and there it remained for a very long time.

After all, he had been expecting something like this to happen ever since he decided to invent time travel.

Then, without a word, he touched his index finger to the paper. Black swirls flowed out from his fingertip, brushing over the enigmatic words and replacing them with a blurred yet graceful pattern – an imprint of the magic his failed experiment had left in the air. He needed a physical record before the data faded too far. Next, he flipped the page over, and swiftly sketched out the shape of the burns in the field. They would fade more slowly than the magical trace, but nature would nevertheless have reasserted its dominance over the countryside long before he got the chance to sit down and interpret the results of his experiment.

Because, as interesting as it would be, he had already been side-tracked for far too long. He knew the Gate of Time couldn't reunite him with his brother. It was a curiosity, nothing more. The laws of time travel deserved to be studied in their own right… but at the same time, they could wait. Seeing Natsu again was far more important than achieving world-renown as the man who invented time travel. Then, when he was living happily with his brother, he would become famous as the greatest genius who had ever lived.

Stowing the record of his failed time travel experiment safely back in his pocket, he set off in the direction of the city – and his Academy, and his study, and his library, and all the half-finished reports on speculative resurrection spells he had left there.

"7th July, X791, huh?" he said to himself, and a smile spread across his face. "Bet I can do it sooner."

* * *

 _ **A/N:** The end! Thanks for reading. I really wanted to do a happy ending for Zeref for a change, so there we are. A huge thank you as always to everyone who has reviewed, followed, favourited, or supported me through this short story, and I really hope you enjoyed it! ~CS_


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